Detection rules › Sigma

Sigma rules: 3f

RuleSeverity
ADCS - Certighost CDC Chase Certificate Request (CVE-2026-54121)high
Application URI Configuration Changeshigh
AWS EFS Fileshare Modified or Deletedmedium
Bitbucket Global Permission Changedmedium
Disabled guest or builtin account activatedmedium
Enumerate All Information With Whoami.EXEmedium
EVTX Created In Uncommon Locationmedium
HackTool - Covenant PowerShell Launcherhigh
HackTool - QuarksPwDump Dump Filecritical
Lateral movement by mounting a network share - net use (command)medium
LoadBalancer Security Group Modificationmedium
New Federated Domain Added - Exchangemedium
New Outlook Macro Createdmedium
Outbound Network Connection Initiated By Microsoft Dialerhigh
Potential Exploitation of CVE-2022-21919 or CVE-2021-34484 for LPElow
Potential Privilege Escalation via Service Permissions Weaknesshigh
Potential Ransomware Activity Using LegalNotice Messagehigh
Potential Xterm Reverse Shellmedium
Potentially Suspicious Rundll32 Activitymedium
PUA - NPS Tunneling Tool Executionhigh
Remove Exported Mailbox from Exchange Webserverhigh
SAM database user credentials dump with Mimikatzhigh
SQL Server xp_cmdshell activation (native event)high
Stop Windows Service Via Net.EXElow
Suspicious Execution of Systeminfolow
Suspicious Get-Variable.exe Creationhigh
Suspicious Scheduled Task Write to System32 Taskshigh
Suspicious Screensaver Binary File Creationmedium
Sysinternals PsSuspend Executionmedium
Triple Cross eBPF Rootkit Default LockFilehigh
Unusual Child Process of dns.exehigh
WMIC Loading Scripting Librariesmedium

ADCS - Certighost CDC Chase Certificate Request (CVE-2026-54121)

#
Status
experimental
Severity
high
Author
Swachchhanda Shrawan Poudel (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects Active Directory Certificate Services (ADCS) certificate requests that include the 'cdc' (Client DC) request attribute pointing to a domain or IP that is not a known Domain Controller. 'cdc' is an optional MS-WCCE enrollment attribute designed for cross-domain/cross-forest scenarios where a client in a child domain tells the CA which DC to contact for identity lookups when the CA cannot reach that domain directly. Legitimate values are DC hostnames or IPs that resolve to a real Domain Controller computer object in AD with the SERVER_TRUST_ACCOUNT (0x2000) userAccountControl bit set. In an attack, the attacker sets cdc to a domain or IP they control so the CA connects to their rogue SMB and LDAP services instead of a real DC. The rogue server returns a forged DC identity which the pre-patch CA accepts without validation. A malicious event looks like: Requester: DOMAIN\GHOST<random>$ Attributes: cdc:<attacker_ip> rmd:<target_dc_fqdn> SubjectAlternativeName: DNS Name=<target_dc_fqdn> CVE-2026-54121 (Certighost) is the known exploit for this path. The July 2026 patch added _ValidateChaseTargetIsDC which rejects cdc values that do not resolve to a legitimate DC object in Active Directory before following the chase.

MITRE ATT&CK Coverage

TacticTechniques
Credential Access

Telemetry Coverage

Rule Body

title: ADCS - Certighost CDC Chase Certificate Request (CVE-2026-54121)
id: c4a1f389-2e6b-4d9a-8f0c-b73e5a12d947
related:
    - id: 2a9e4f17-6c3b-4d8a-e1f0-b57c2d94a631
      type: similar
status: experimental
description: |
    Detects Active Directory Certificate Services (ADCS) certificate requests that include the
    'cdc' (Client DC) request attribute pointing to a domain or IP that is not a known Domain Controller.

    'cdc' is an optional MS-WCCE enrollment attribute designed for cross-domain/cross-forest
    scenarios where a client in a child domain tells the CA which DC to contact for identity
    lookups when the CA cannot reach that domain directly. Legitimate values are DC hostnames
    or IPs that resolve to a real Domain Controller computer object in AD with the
    SERVER_TRUST_ACCOUNT (0x2000) userAccountControl bit set.

    In an attack, the attacker sets cdc to a domain or IP they control so the CA connects to their
    rogue SMB and LDAP services instead of a real DC. The rogue server returns a forged DC
    identity which the pre-patch CA accepts without validation. A malicious event looks like:

        Requester: DOMAIN\GHOST<random>$
        Attributes: cdc:<attacker_ip>
                    rmd:<target_dc_fqdn>
        SubjectAlternativeName: DNS Name=<target_dc_fqdn>

    CVE-2026-54121 (Certighost) is the known exploit for this path. The July 2026 patch added
    _ValidateChaseTargetIsDC which rejects cdc values that do not resolve to a legitimate
    DC object in Active Directory before following the chase.
references:
    - https://github.com/aniqfakhrul/CVE-2026-54121
    - https://gist.github.com/H0j3n/a5ef2609b5f2944ac2390a191a534c26
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2026-07-27
tags:
    - attack.privilege-escalation
    - attack.credential-access
    - attack.t1649
    - cve.2026-54121
    - detection.emerging-threats
logsource:
    product: windows
    service: security
    definition: |
        This requires two independent controls on the CA server.
            (1) CA\AuditFilter must have bit 0x04 (AUDIT_CERTSRV_REQUESTFLAGS) set
                this instructs certsrv.exe to emit request/issuance events.
                Without this bit the CA never calls ReportEvent() for certificate operations, regardless of OS policy.
                    - Set via: certutil -setreg CA\AuditFilter 127 then net stop CertSvc; net start CertSvc.
            (2) The OS audit subcategory must be enabled to write those events into the Security log:
                auditpol /set /subcategory:"Certification Services" /success:enable.
        Note: GPO alone (without AuditFilter) is not sufficient.
detection:
    selection:
        EventID: 4886
        Attributes|contains: 'cdc:'
    filter_main_known_cdc:
        Attributes|contains|expand: '%known_cdcs%'  # should be populated with all known legitimate DC hostnames and IPs
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_*

Stage 1: selection

selection:
    EventID: 4886
    Attributes|contains: 'cdc:'

Stage 2: not filter_main_known_cdc

filter_main_known_cdc:
    Attributes|contains|expand: '%known_cdcs%'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Attributesmatch
  • cdc: corpus 2 (sigma 2)
field:"Attributes" kind:match value:"cdc:"

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
Attributesmatch%known_cdcs%excludes:Attributes field:"Attributes" value:"%known_cdcs%"

Application URI Configuration Changes

#
Status
test
Severity
high
Author
Mark Morowczynski '@markmorow', Bailey Bercik '@baileybercik'
Source
github.com/SigmaHQ/sigma

Detects when a configuration change is made to an applications URI. URIs for domain names that no longer exist (dangling URIs), not using HTTPS, wildcards at the end of the domain, URIs that are no unique to that app, or URIs that point to domains you do not control should be investigated.

Known False Positives

  • When and administrator is making legitimate URI configuration changes to an application. This should be a planned event.

MITRE ATT&CK Coverage

Telemetry Coverage

Rules Detecting the Same Action

These rules filter on the same operation.

Rule Body

title: Application URI Configuration Changes
id: 0055ad1f-be85-4798-83cf-a6da17c993b3
status: test
description: |
    Detects when a configuration change is made to an applications URI.
    URIs for domain names that no longer exist (dangling URIs), not using HTTPS, wildcards at the end of the domain, URIs that are no unique to that app, or URIs that point to domains you do not control should be investigated.
references:
    - https://learn.microsoft.com/en-us/entra/architecture/security-operations-applications#application-configuration-changes
author: Mark Morowczynski '@markmorow', Bailey Bercik '@baileybercik'
date: 2022-06-02
tags:
    - attack.initial-access
    - attack.stealth
    - attack.t1528
    - attack.t1078.004
    - attack.persistence
    - attack.credential-access
    - attack.privilege-escalation
logsource:
    product: azure
    service: auditlogs
detection:
    selection:
        properties.message: Update Application Sucess- Property Name AppAddress
    condition: selection
falsepositives:
    - When and administrator is making legitimate URI configuration changes to an application. This should be a planned event.
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    properties.message: Update Application Sucess- Property Name AppAddress

Indicators

These rows show field, operator, and value matches.

AWS EFS Fileshare Modified or Deleted

#
Status
test
Severity
medium
Author
Austin Songer @austinsonger
Source
github.com/SigmaHQ/sigma

Detects when a EFS Fileshare is modified or deleted. You can't delete a file system that is in use. If the file system has any mount targets, the adversary must first delete them, so deletion of a mount will occur before deletion of a fileshare.

MITRE ATT&CK Coverage

TacticTechniques
ImpactNo specific technique

Telemetry Coverage

Rules Detecting the Same Action

These rules filter on the same operation.

Rule Body

title: AWS EFS Fileshare Modified or Deleted
id: 25cb1ba1-8a19-4a23-a198-d252664c8cef
status: test
description: |
  Detects when a EFS Fileshare is modified or deleted.
  You can't delete a file system that is in use.
  If the file system has any mount targets, the adversary must first delete them, so deletion of a mount will occur before deletion of a fileshare.
references:
    - https://docs.aws.amazon.com/efs/latest/ug/API_DeleteFileSystem.html
author: Austin Songer @austinsonger
date: 2021-08-15
modified: 2022-10-09
tags:
    - attack.impact
logsource:
    product: aws
    service: cloudtrail
detection:
    selection:
        eventSource: elasticfilesystem.amazonaws.com
        eventName: DeleteFileSystem
    condition: selection
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    eventSource: elasticfilesystem.amazonaws.com
    eventName: DeleteFileSystem

Indicators

These rows show field, operator, and value matches.

Bitbucket Global Permission Changed

#
Status
test
Severity
medium
Author
Muhammad Faisal (@faisalusuf)
Source
github.com/SigmaHQ/sigma

Detects global permissions change activity.

Known False Positives

  • Legitimate user activity.

MITRE ATT&CK Coverage

TacticTechniques
Persistence
Privilege Escalation

Rule Body

title: Bitbucket Global Permission Changed
id: aac6c4f4-87c7-4961-96ac-c3fd3a42c310
status: test
description: Detects global permissions change activity.
references:
    - https://confluence.atlassian.com/bitbucketserver/audit-log-events-776640423.html
    - https://confluence.atlassian.com/bitbucketserver/global-permissions-776640369.html
author: Muhammad Faisal (@faisalusuf)
date: 2024-02-25
tags:
    - attack.persistence
    - attack.privilege-escalation
    - attack.t1098
logsource:
    product: bitbucket
    service: audit
    definition: 'Requirements: "Advance" log level is required to receive these audit events.'
detection:
    selection:
        auditType.category: 'Permissions'
        auditType.action:
            - 'Global permission remove request'
            - 'Global permission removed'
            - 'Global permission granted'
            - 'Global permission requested'
    condition: selection
falsepositives:
    - Legitimate user activity.
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    auditType.category: 'Permissions'
    auditType.action:
        - 'Global permission remove request'
        - 'Global permission removed'
        - 'Global permission granted'
        - 'Global permission requested'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
auditType.actioneq
  • Global permission granted
  • Global permission remove request
  • Global permission removed
  • Global permission requested
field:"auditType.action" kind:eq
auditType.categoryeq
  • Permissions
field:"auditType.category" kind:eq value:"Permissions"

Disabled guest or builtin account activated

#
Status
experimental
Severity
medium
Author
mdecrevoisier
Source
github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker enables a disabled builtin account.

Known False Positives

  • SYSPREP deployement
  • Usage of Remote assistance

MITRE ATT&CK Coverage

TacticTechniques
Persistence

Telemetry Coverage

Rule Body

title: Disabled guest or builtin account activated
description: Detects scenarios where an attacker enables a disabled builtin account.
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0003-Persistence/T1136-Create%20account
- https://www.stigviewer.com/stig/windows_xp/2013-03-14/finding/V-3369
tags:
- attack.persistence
- attack.t1098
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  service: security
detection:
  selection_event:
    EventID: 4722
  selection_username:
    TargetUserName:
      - Guest
      - DefaultAccount
      - support_388945a0   # Remote assistance
      - HelpAssistant      # Managed by Remote Desktop Help Session Manager service
      - WDAGUtilityAccount # Defender Application Guard
  selection_user_sid:
    TargetUserSid|endswith:
      - '-501' # Guest account
      - '-503' # DefaultAccount (DSMA) starting Windows 10.1607
      - '1001' # support_388945a0
  condition: selection_event and (selection_username or selection_user_sid)
falsepositives:
- SYSPREP deployement
- Usage of Remote assistance
level: medium

Stages and Predicates

Stage 0: condition

selection_event and (selection_username or selection_user_sid)

Stage 1: selection_event

selection_event:
  EventID: 4722

Stage 2: selection_username

selection_username:
  TargetUserName:
    - Guest
    - DefaultAccount
    - support_388945a0
    - HelpAssistant
    - WDAGUtilityAccount

Stage 3: selection_user_sid

selection_user_sid:
  TargetUserSid|endswith:
    - '-501'
    - '-503'
    - '1001'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
TargetUserNameeq
  • DefaultAccount
  • Guest
  • HelpAssistant
  • WDAGUtilityAccount
  • support_388945a0
field:"TargetUserName" kind:eq
TargetUserSidends_with
  • -501
  • -503
  • 1001
field:"TargetUserSid" kind:ends_with

Enumerate All Information With Whoami.EXE

#
Status
test
Severity
medium
Author
Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects the execution of "whoami.exe" with the "/all" flag

MITRE ATT&CK Coverage

TacticTechniques
Discovery

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: Enumerate All Information With Whoami.EXE
id: c248c896-e412-4279-8c15-1c558067b6fa
status: test
description: Detects the execution of "whoami.exe" with the "/all" flag
references:
    - https://brica.de/alerts/alert/public/1247926/agent-tesla-keylogger-delivered-inside-a-power-iso-daa-archive/
    - https://app.any.run/tasks/7eaba74e-c1ea-400f-9c17-5e30eee89906/
    - https://www.youtube.com/watch?v=DsJ9ByX84o4&t=6s
author: Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)
date: 2023-12-04
modified: 2024-03-05
tags:
    - attack.discovery
    - attack.t1033
    - car.2016-03-001
logsource:
    category: process_creation
    product: windows
detection:
    selection_main_img:
        - Image|endswith: '\whoami.exe'
        - OriginalFileName: 'whoami.exe'
    selection_main_cli:
        CommandLine|contains|windash: ' -all'
    condition: all of selection_main_*
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

all of selection_main_*

Stage 1: selection_main_img

selection_main_img:
    - Image|endswith: '\whoami.exe'
    - OriginalFileName: 'whoami.exe'

Stage 2: selection_main_cli

selection_main_cli:
    CommandLine|contains|windash: ' -all'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • -all corpus 2 (sigma 2)
  • /all corpus 2 (sigma 2)
  • –all
  • —all
  • ―all
field:"CommandLine" kind:match
Imageends_with
  • \whoami.exe corpus 19 (sigma 19)
field:"Image" kind:ends_with value:"\whoami.exe"
OriginalFileNameeq
  • whoami.exe corpus 11 (sigma 9, elastic 1, splunk 1)
field:"OriginalFileName" kind:eq value:"whoami.exe"

EVTX Created In Uncommon Location

#
Status
test
Severity
medium
Author
D3F7A5105
Source
github.com/SigmaHQ/sigma

Detects the creation of new files with the ".evtx" extension in non-common or non-standard location. This could indicate tampering with default EVTX locations in order to evade security controls or simply exfiltration of event log to search for sensitive information within. Note that backup software and legitimate administrator might perform similar actions during troubleshooting.

Known False Positives

  • Administrator or backup activity
  • An unknown bug seems to trigger the Windows "svchost" process to drop EVTX files in the "C:\Windows\Temp" directory in the form "<log_name">_<uuid>.evtx". See https://superuser.com/questions/1371229/low-disk-space-after-filling-up-c-windows-temp-with-evtx-and-txt-files

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 11: FileCreate

Rule Body

title: EVTX Created In Uncommon Location
id: 65236ec7-ace0-4f0c-82fd-737b04fd4dcb
status: test
description: |
    Detects the creation of new files with the ".evtx" extension in non-common or non-standard location.
    This could indicate tampering with default EVTX locations in order to evade security controls or simply exfiltration of event log to search for sensitive information within.
    Note that backup software and legitimate administrator might perform similar actions during troubleshooting.
references:
    - https://learn.microsoft.com/en-us/windows/win32/eventlog/eventlog-key
author: D3F7A5105
date: 2023-01-02
modified: 2024-03-26
tags:
    - attack.defense-impairment
    - attack.t1685.001
logsource:
    category: file_event
    product: windows
    definition: 'Requirements: The ".evtx" extension should be monitored via a Sysmon configuration. Example: <TargetFilename condition="end with">.evtx<TargetFilename>'
detection:
    selection:
        TargetFilename|endswith: '.evtx'
    filter_main_path:
        TargetFilename|startswith: 'C:\Windows\System32\winevt\Logs\'
    filter_main_baseimage:
        TargetFilename|startswith: 'C:\ProgramData\Microsoft\Windows\Containers\BaseImages\'
        TargetFilename|endswith: '\Windows\System32\winevt\Logs\'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Administrator or backup activity
    - An unknown bug seems to trigger the Windows "svchost" process to drop EVTX files in the "C:\Windows\Temp" directory in the form "<log_name">_<uuid>.evtx". See https://superuser.com/questions/1371229/low-disk-space-after-filling-up-c-windows-temp-with-evtx-and-txt-files
level: medium
regression_tests_path: regression_data/rules/windows/file/file_event/file_event_win_create_evtx_non_common_locations/info.yml

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_*

Stage 1: selection

selection:
    TargetFilename|endswith: '.evtx'

Stage 2: not filter_main_*

filter_main_path:
    TargetFilename|startswith: 'C:\Windows\System32\winevt\Logs\'
filter_main_baseimage:
    TargetFilename|startswith: 'C:\ProgramData\Microsoft\Windows\Containers\BaseImages\'
    TargetFilename|endswith: '\Windows\System32\winevt\Logs\'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
TargetFilenameends_with
  • .evtx corpus 2 (sigma 2)
field:"TargetFilename" kind:ends_with value:".evtx"

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
TargetFilenameends_with\Windows\System32\winevt\Logs\excludes:TargetFilename field:"TargetFilename" value:"\Windows\System32\winevt\Logs\"
TargetFilenamestarts_withC:\ProgramData\Microsoft\Windows\Containers\BaseImages\excludes:TargetFilename field:"TargetFilename" value:"C:\ProgramData\Microsoft\Windows\Containers\BaseImages\"
TargetFilenamestarts_withC:\Windows\System32\winevt\Logs\excludes:TargetFilename field:"TargetFilename" value:"C:\Windows\System32\winevt\Logs\"

HackTool - Covenant PowerShell Launcher

#
Status
test
Severity
high
Author
Florian Roth (Nextron Systems), Jonhnathan Ribeiro, oscd.community
Source
github.com/SigmaHQ/sigma

Detects suspicious command lines used in Covenant luanchers

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: HackTool - Covenant PowerShell Launcher
id: c260b6db-48ba-4b4a-a76f-2f67644e99d2
status: test
description: Detects suspicious command lines used in Covenant luanchers
references:
    - https://posts.specterops.io/covenant-v0-5-eee0507b85ba
author: Florian Roth (Nextron Systems), Jonhnathan Ribeiro, oscd.community
date: 2020-06-04
modified: 2023-02-21
tags:
    - attack.execution
    - attack.stealth
    - attack.t1059.001
    - attack.t1564.003
logsource:
    category: process_creation
    product: windows
detection:
    selection_1:
        CommandLine|contains|all:
            - '-Sta'
            - '-Nop'
            - '-Window'
            - 'Hidden'
        CommandLine|contains:
            - '-Command'
            - '-EncodedCommand'
    selection_2:
        CommandLine|contains:
            - 'sv o (New-Object IO.MemorySteam);sv d '
            - 'mshta file.hta'
            - 'GruntHTTP'
            - '-EncodedCommand cwB2ACAAbwAgA'
    condition: 1 of selection_*
level: high

Stages and Predicates

Stage 0: condition

1 of selection_*

Stage 1: selection_1

selection_1:
    CommandLine|contains|all:
        - '-Sta'
        - '-Nop'
        - '-Window'
        - 'Hidden'
    CommandLine|contains:
        - '-Command'
        - '-EncodedCommand'

Stage 2: selection_2

selection_2:
    CommandLine|contains:
        - 'sv o (New-Object IO.MemorySteam);sv d '
        - 'mshta file.hta'
        - 'GruntHTTP'
        - '-EncodedCommand cwB2ACAAbwAgA'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • -Command corpus 2 (sigma 2)
  • -EncodedCommand corpus 3 (elastic 2, sigma 1)
  • -EncodedCommand cwB2ACAAbwAgA
  • -Nop corpus 2 (sigma 2)
  • -Sta
  • -Window
  • GruntHTTP
  • Hidden corpus 4 (sigma 4)
  • mshta file.hta
  • sv o (New-Object IO.MemorySteam);sv d
field:"CommandLine" kind:match

HackTool - QuarksPwDump Dump File

#
Status
test
Severity
critical
Author
Florian Roth (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects a dump file written by QuarksPwDump password dumper

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 11: FileCreate

Rule Body

title: HackTool - QuarksPwDump Dump File
id: 847def9e-924d-4e90-b7c4-5f581395a2b4
status: test
description: Detects a dump file written by QuarksPwDump password dumper
references:
    - https://jpcertcc.github.io/ToolAnalysisResultSheet/details/QuarksPWDump.htm
author: Florian Roth (Nextron Systems)
date: 2018-02-10
modified: 2024-06-27
tags:
    - attack.credential-access
    - attack.t1003.002
logsource:
    category: file_event
    product: windows
detection:
    selection:
        TargetFilename|contains|all:
            - '\AppData\Local\Temp\SAM-'
            - '.dmp'
    condition: selection
falsepositives:
    - Unknown
level: critical

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    TargetFilename|contains|all:
        - '\AppData\Local\Temp\SAM-'
        - '.dmp'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
TargetFilenamematch
  • .dmp corpus 3 (sigma 3)
  • \AppData\Local\Temp\SAM-
field:"TargetFilename" kind:match

Lateral movement by mounting a network share - net use (command)

#
Status
experimental
Severity
medium
Author
mdecrevoisier
Source
github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker attempts to move laterally by mounting a network share using compromised user credentials.

Known False Positives

  • Administrator activity

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Lateral movement by mounting a network share - net use (command)
description: Detects scenarios where an attacker attempts to move laterally by mounting a network share using compromised user credentials.
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0008-Lateral%20Movement/T1021.002%20-SMB%20Windows%20Admin%20Shares
- https://imphash.medium.com/detecting-lateral-movement-101-tracking-movement-smb-windows-admin-shares-through-windows-log-6005e3ba6980
- https://stealthbits.com/blog/how-to-detect-pass-the-hash-attacks/
- https://attack.mitre.org/software/S0039/
tags:
- attack.lateral_movement
- attack.t1021.002
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  service: security
detection: # Full command example: 'net use m: \\<dst-server>\c$ /USER:<compromised_user> <credentials>'
  selection_command:
    EventID: 4688
    NewProcessName|endswith:
      - \net1.exe
      - \net.exe
    CommandLine|contains|all:
      - net
      - use
      - '/user:'

  #selection_swtich_cred:
    #EventID: 4648
    #TargetInfo|startswith: cifs

  condition: selection_command # optional[and selection_swtich_cred]. Correlate both events with SubjectUserName and SubjectLogonId
falsepositives:
- Administrator activity
level: medium

Stages and Predicates

Stage 0: condition

selection_command # optional[and selection_swtich_cred]. Correlate both events with SubjectUserName and SubjectLogonId

Stage 1: selection_command

selection_command:
  EventID: 4688
  NewProcessName|endswith:
    - \net1.exe
    - \net.exe
  CommandLine|contains|all:
    - net
    - use
    - '/user:'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • /user: corpus 6 (sigma 5, splunk 1)
  • net corpus 7 (sigma 7)
  • use corpus 3 (sigma 2, splunk 1)
field:"CommandLine" kind:match
NewProcessNameends_with
  • \net.exe corpus 49 (sigma 49)
  • \net1.exe corpus 47 (sigma 47)
field:"Image" kind:ends_with

LoadBalancer Security Group Modification

#
Status
test
Severity
medium
Author
jamesc-grafana
Source
github.com/SigmaHQ/sigma

Detects changes to the security groups associated with an Elastic Load Balancer (ELB) or Application Load Balancer (ALB). This can indicate that a misconfiguration allowing more traffic into the system than required, or could indicate that an attacker is attempting to enable new connections into a VPC or subnet controlled by the account.

Known False Positives

  • Repurposing of an ELB or ALB to serve a different or additional application
  • Changes to security groups to allow for new services to be deployed

MITRE ATT&CK Coverage

TacticTechniques
Initial Access

Telemetry Coverage

Rule Body

title: LoadBalancer Security Group Modification
id: 7a4409fc-f8ca-45f6-8006-127d779eaad9
status: test
description: |
    Detects changes to the security groups associated with an Elastic Load Balancer (ELB) or Application Load Balancer (ALB).
    This can indicate that a misconfiguration allowing more traffic into the system than required, or could indicate that an attacker is attempting to enable new connections into a VPC or subnet controlled by the account.
references:
    - https://www.gorillastack.com/blog/real-time-events/important-aws-cloudtrail-security-events-tracking/
author: jamesc-grafana
date: 2024-07-11
tags:
    - attack.initial-access
    - attack.t1190
logsource:
    product: aws
    service: cloudtrail
detection:
    selection:
        eventSource: 'elasticloadbalancing.amazonaws.com'
        eventName:
            - 'ApplySecurityGroupsToLoadBalancer'
            - 'SetSecurityGroups'
    condition: selection
falsepositives:
    - Repurposing of an ELB or ALB to serve a different or additional application
    - Changes to security groups to allow for new services to be deployed
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    eventSource: 'elasticloadbalancing.amazonaws.com'
    eventName:
        - 'ApplySecurityGroupsToLoadBalancer'
        - 'SetSecurityGroups'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
eventNameeq
  • ApplySecurityGroupsToLoadBalancer
  • SetSecurityGroups
field:"aws::eventName" kind:eq
eventSourceeq
  • elasticloadbalancing.amazonaws.com
field:"aws::eventSource" kind:eq value:"elasticloadbalancing.amazonaws.com"

New Federated Domain Added - Exchange

#
Status
test
Severity
medium
Author
Splunk Threat Research Team (original rule), '@ionsor (rule)'
Source
github.com/SigmaHQ/sigma

Detects the addition of a new Federated Domain.

Known False Positives

  • The creation of a new Federated domain is not necessarily malicious, however these events need to be followed closely, as it may indicate federated credential abuse or backdoor via federated identities at a similar or different cloud provider.

MITRE ATT&CK Coverage

TacticTechniques
Persistence

Telemetry Coverage

Rules Detecting the Same Action

These rules filter on the same operation.

Rule Body

title: New Federated Domain Added - Exchange
id: 42127bdd-9133-474f-a6f1-97b6c08a4339
related:
    - id: 58f88172-a73d-442b-94c9-95eaed3cbb36
      type: similar
status: test
description: Detects the addition of a new Federated Domain.
references:
    - https://www.fireeye.com/content/dam/fireeye-www/blog/pdfs/wp-m-unc2452-2021-000343-01.pdf
    - https://us-cert.cisa.gov/ncas/alerts/aa21-008a
    - https://www.splunk.com/en_us/blog/security/a-golden-saml-journey-solarwinds-continued.html
    - https://www.sygnia.co/golden-saml-advisory
    - https://o365blog.com/post/aadbackdoor/
author: Splunk Threat Research Team (original rule), '@ionsor (rule)'
date: 2022-02-08
tags:
    - attack.persistence
    - attack.t1136.003
logsource:
    service: exchange
    product: m365
detection:
    selection:
        eventSource: Exchange
        eventName: 'Add-FederatedDomain'
        status: success
    condition: selection
falsepositives:
    - The creation of a new Federated domain is not necessarily malicious, however these events need to be followed closely, as it may indicate federated credential abuse or backdoor via federated identities at a similar or different cloud provider.
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    eventSource: Exchange
    eventName: 'Add-FederatedDomain'
    status: success

Indicators

These rows show field, operator, and value matches.

New Outlook Macro Created

#
Status
test
Severity
medium
Author
@ScoubiMtl
Source
github.com/SigmaHQ/sigma

Detects the creation of a macro file for Outlook.

Known False Positives

  • User genuinely creates a VB Macro for their email

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 11: FileCreate

Rule Body

title: New Outlook Macro Created
id: 8c31f563-f9a7-450c-bfa8-35f8f32f1f61
related:
    - id: 117d3d3a-755c-4a61-b23e-9171146d094c
      type: derived
status: test
description: Detects the creation of a macro file for Outlook.
references:
    - https://www.mdsec.co.uk/2020/11/a-fresh-outlook-on-mail-based-persistence/
author: '@ScoubiMtl'
date: 2021-04-05
modified: 2023-02-08
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.command-and-control
    - attack.t1137
    - attack.t1008
    - attack.t1546
logsource:
    category: file_event
    product: windows
detection:
    selection:
        Image|endswith: '\outlook.exe'
        TargetFilename|endswith: '\Microsoft\Outlook\VbaProject.OTM'
    condition: selection
falsepositives:
    - User genuinely creates a VB Macro for their email
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith: '\outlook.exe'
    TargetFilename|endswith: '\Microsoft\Outlook\VbaProject.OTM'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \outlook.exe corpus 13 (sigma 13)
field:"Image" kind:ends_with value:"\outlook.exe"
TargetFilenameends_with
  • \Microsoft\Outlook\VbaProject.OTM corpus 2 (sigma 2)
field:"TargetFilename" kind:ends_with value:"\Microsoft\Outlook\VbaProject.OTM"

Outbound Network Connection Initiated By Microsoft Dialer

#
Status
test
Severity
high
Author
CertainlyP
Source
github.com/SigmaHQ/sigma

Detects outbound network connection initiated by Microsoft Dialer. The Microsoft Dialer, also known as Phone Dialer, is a built-in utility application included in various versions of the Microsoft Windows operating system. Its primary function is to provide users with a graphical interface for managing phone calls via a modem or a phone line connected to the computer. This is an outdated process in the current conext of it's usage and is a common target for info stealers for process injection, and is used to make C2 connections, common example is "Rhadamanthys"

Known False Positives

  • In Modern Windows systems, unable to see legitimate usage of this process, However, if an organization has legitimate purpose for this there can be false positives.

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 3: Network connection

Rule Body

title: Outbound Network Connection Initiated By Microsoft Dialer
id: 37e4024a-6c80-4d8f-b95d-2e7e94f3a8d1
status: test
description: |
    Detects outbound network connection initiated by Microsoft Dialer.
    The Microsoft Dialer, also known as Phone Dialer, is a built-in utility application included in various versions of the Microsoft Windows operating system. Its primary function is to provide users with a graphical interface for managing phone calls via a modem or a phone line connected to the computer.
    This is an outdated process in the current conext of it's usage and is a common target for info stealers for process injection, and is used to make C2 connections, common example is "Rhadamanthys"
references:
    - https://tria.ge/240301-rk34sagf5x/behavioral2
    - https://app.any.run/tasks/6720b85b-9c53-4a12-b1dc-73052a78477d
    - https://research.checkpoint.com/2023/rhadamanthys-v0-5-0-a-deep-dive-into-the-stealers-components/
    - https://strontic.github.io/xcyclopedia/library/dialer.exe-0B69655F912619756C704A0BF716B61F.html
author: CertainlyP
date: 2024-04-26
tags:
    - attack.execution
    - attack.command-and-control
    - attack.t1071.001
logsource:
    category: network_connection
    product: windows
detection:
    selection:
        Image|endswith: ':\Windows\System32\dialer.exe'
        Initiated: 'true'
    filter_main_local_ranges:
        DestinationIp|cidr:
            - '127.0.0.0/8'
            - '10.0.0.0/8'
            - '172.16.0.0/12'
            - '192.168.0.0/16'
            - '169.254.0.0/16'
            - '::1/128'  # IPv6 loopback
            - 'fe80::/10'  # IPv6 link-local addresses
            - 'fc00::/7'  # IPv6 private addresses
    condition: selection and not 1 of filter_main_*
falsepositives:
    - In Modern Windows systems, unable to see legitimate usage of this process, However, if an organization has legitimate purpose for this there can be false positives.
level: high

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_*

Stage 1: selection

selection:
    Image|endswith: ':\Windows\System32\dialer.exe'
    Initiated: 'true'

Stage 2: not filter_main_local_ranges

filter_main_local_ranges:
    DestinationIp|cidr:
        - '127.0.0.0/8'
        - '10.0.0.0/8'
        - '172.16.0.0/12'
        - '192.168.0.0/16'
        - '169.254.0.0/16'
        - '::1/128'
        - 'fe80::/10'
        - 'fc00::/7'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • :\Windows\System32\dialer.exe
field:"Image" kind:ends_with value:":\Windows\System32\dialer.exe"
Initiatedeq
  • true corpus 50 (sigma 50)
field:"Initiated" kind:eq value:"true"

Exclusions

The rule actively suppresses these predicates.

Potential Exploitation of CVE-2022-21919 or CVE-2021-34484 for LPE

#
Status
test
Severity
low
Author
Cybex
Source
github.com/SigmaHQ/sigma

Detects potential exploitation attempts of CVE-2022-21919 or CVE-2021-34484 leading to local privilege escalation via the User Profile Service. During exploitation of this vulnerability, two logs (Provider_Name: Microsoft-Windows-User Profiles Service) with EventID 1511 and 1515 are created (EventID 1515 may generate many false positives). Additionally, the directory \Users\TEMP may be created during exploitation. This behavior was observed on Windows Server 2008.

Known False Positives

  • Corrupted user profiles - https://social.technet.microsoft.com/wiki/contents/articles/3571.windows-user-profiles-service-event-1511-windows-cannot-find-the-local-profile-and-is-logging-you-on-with-a-temporary-profile.aspx

MITRE ATT&CK Coverage

TacticTechniques
ExecutionNo specific technique

Telemetry Coverage

Rule Body

title: Potential Exploitation of CVE-2022-21919 or CVE-2021-34484 for LPE
id: 52a85084-6989-40c3-8f32-091e12e17692
status: test
description: |
    Detects potential exploitation attempts of CVE-2022-21919 or CVE-2021-34484 leading to local privilege escalation via the User Profile Service.
    During exploitation of this vulnerability, two logs (Provider_Name: Microsoft-Windows-User Profiles Service) with EventID 1511 and 1515 are created (EventID 1515 may generate many false positives).
    Additionally, the directory \Users\TEMP may be created during exploitation. This behavior was observed on Windows Server 2008.
references:
    - https://packetstormsecurity.com/files/166692/Windows-User-Profile-Service-Privlege-Escalation.html
author: Cybex
date: 2022-08-16
modified: 2025-11-03
tags:
    - attack.execution
    - detection.emerging-threats
    - cve.2022-21919
    - cve.2021-34484
logsource:
    product: windows
    service: application
detection:
    selection:
        EventID: 1511
        Provider_Name: 'Microsoft-Windows-User Profiles Service'
    condition: selection
falsepositives:
    - Corrupted user profiles - https://social.technet.microsoft.com/wiki/contents/articles/3571.windows-user-profiles-service-event-1511-windows-cannot-find-the-local-profile-and-is-logging-you-on-with-a-temporary-profile.aspx
level: low

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    EventID: 1511
    Provider_Name: 'Microsoft-Windows-User Profiles Service'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Provider_Nameeq
  • Microsoft-Windows-User Profiles Service
field:"Provider_Name" kind:eq value:"Microsoft-Windows-User Profiles Service"

Potential Privilege Escalation via Service Permissions Weakness

#
Status
test
Severity
high
Author
Teymur Kheirkhabarov
Source
github.com/SigmaHQ/sigma

Detect modification of services configuration (ImagePath, FailureCommand and ServiceDLL) in registry by processes with Medium integrity level

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Potential Privilege Escalation via Service Permissions Weakness
id: 0f9c21f1-6a73-4b0e-9809-cb562cb8d981
status: test
description: Detect modification of services configuration (ImagePath, FailureCommand and ServiceDLL) in registry by processes with Medium integrity level
references:
    - https://speakerdeck.com/heirhabarov/hunting-for-privilege-escalation-in-windows-environment
    - https://pentestlab.blog/2017/03/31/insecure-registry-permissions/
author: Teymur Kheirkhabarov
date: 2019-10-26
modified: 2024-12-01
tags:
    - attack.persistence
    - attack.privilege-escalation
    - attack.execution
    - attack.stealth
    - attack.t1574.011
logsource:
    product: windows
    category: process_creation
detection:
    selection:
        IntegrityLevel:
            - 'Medium'
            - 'S-1-16-8192'
        CommandLine|contains|all:
            - 'ControlSet'
            - 'services'
        CommandLine|contains:
            - '\ImagePath'
            - '\FailureCommand'
            - '\ServiceDll'
    condition: selection
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    IntegrityLevel:
        - 'Medium'
        - 'S-1-16-8192'
    CommandLine|contains|all:
        - 'ControlSet'
        - 'services'
    CommandLine|contains:
        - '\ImagePath'
        - '\FailureCommand'
        - '\ServiceDll'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • ControlSet corpus 3 (sigma 3)
  • \FailureCommand
  • \ImagePath
  • \ServiceDll
  • services corpus 3 (sigma 2, splunk 1)
field:"CommandLine" kind:match
IntegrityLeveleq
  • Medium corpus 3 (sigma 3)
  • S-1-16-8192 corpus 3 (sigma 3)
field:"IntegrityLevel" kind:eq

Potential Ransomware Activity Using LegalNotice Message

#
Status
test
Severity
high
Author
frack113
Source
github.com/SigmaHQ/sigma

Detect changes to the "LegalNoticeCaption" or "LegalNoticeText" registry values where the message set contains keywords often used in ransomware ransom messages

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Potential Ransomware Activity Using LegalNotice Message
id: 8b9606c9-28be-4a38-b146-0e313cc232c1
status: test
description: Detect changes to the "LegalNoticeCaption" or "LegalNoticeText" registry values where the message set contains keywords often used in ransomware ransom messages
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/5c1e6f1b4fafd01c8d1ece85f510160fc1275fbf/atomics/T1491.001/T1491.001.md
author: frack113
date: 2022-12-11
modified: 2023-08-17
tags:
    - attack.impact
    - attack.t1491.001
logsource:
    product: windows
    category: registry_set
detection:
    selection:
        TargetObject|contains:
            - '\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\LegalNoticeCaption'
            - '\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\LegalNoticeText'
        Details|contains:
            - 'encrypted'
            - 'Unlock-Password'
            - 'paying'
    condition: selection
falsepositives:
    - Unknown
level: high
simulation:
    - type: atomic-red-team
      name: Configure LegalNoticeCaption and LegalNoticeText registry keys to display ransom message
      technique: T1491.001
      atomic_guid: ffcbfaab-c9ff-470b-928c-f086b326089b
regression_tests_path: regression_data/rules/windows/registry/registry_set/registry_set_legalnotice_susp_message/info.yml

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    TargetObject|contains:
        - '\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\LegalNoticeCaption'
        - '\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\LegalNoticeText'
    Details|contains:
        - 'encrypted'
        - 'Unlock-Password'
        - 'paying'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Detailsmatch
  • Unlock-Password
  • encrypted
  • paying
field:"Details" kind:match
TargetObjectmatch
  • \SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\LegalNoticeCaption
  • \SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\LegalNoticeText
field:"TargetObject" kind:match

Potential Xterm Reverse Shell

#
Status
test
Severity
medium
Author
@d4ns4n_
Source
github.com/SigmaHQ/sigma

Detects usage of "xterm" as a potential reverse shell tunnel

MITRE ATT&CK Coverage

Telemetry Coverage

PlatformRecord / event type
LinuxEvent ID 1: Process Create

Rule Body

title: Potential Xterm Reverse Shell
id: 4e25af4b-246d-44ea-8563-e42aacab006b
status: test
description: Detects usage of "xterm" as a potential reverse shell tunnel
references:
    - https://pentestmonkey.net/cheat-sheet/shells/reverse-shell-cheat-sheet
    - https://www.revshells.com/
author: '@d4ns4n_'
date: 2023-04-24
tags:
    - attack.execution
    - attack.t1059
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        Image|contains: 'xterm'
        CommandLine|contains: '-display'
        CommandLine|endswith: ':1'
    condition: selection
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|contains: 'xterm'
    CommandLine|contains: '-display'
    CommandLine|endswith: ':1'

Indicators

These rows show field, operator, and value matches.

Potentially Suspicious Rundll32 Activity

#
Status
test
Severity
medium
Author
juju4, Jonhnathan Ribeiro, oscd.community, Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects suspicious execution of rundll32, with specific calls to some DLLs with known LOLBIN functionalities

Known False Positives

  • False positives depend on scripts and administrative tools used in the monitored environment

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: Potentially Suspicious Rundll32 Activity
id: e593cf51-88db-4ee1-b920-37e89012a3c9
status: test
description: Detects suspicious execution of rundll32, with specific calls to some DLLs with known LOLBIN functionalities
references:
    - http://www.hexacorn.com/blog/2017/05/01/running-programs-via-proxy-jumping-on-a-edr-bypass-trampoline/
    - https://twitter.com/Hexacorn/status/885258886428725250
    - https://gist.github.com/ryhanson/227229866af52e2d963cf941af135a52
    - https://twitter.com/nas_bench/status/1433344116071583746 # dfshim.dll,ShOpenVerbShortcut
    - https://twitter.com/eral4m/status/1479106975967240209 # scrobj.dll,GenerateTypeLib
    - https://twitter.com/eral4m/status/1479080793003671557 # shimgvw.dll,ImageView_Fullscreen
author: juju4, Jonhnathan Ribeiro, oscd.community, Nasreddine Bencherchali (Nextron Systems)
date: 2019-01-16
modified: 2023-05-17
tags:
    - attack.stealth
    - attack.t1218.011
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        - CommandLine|contains|all:
              - 'javascript:'
              - '.RegisterXLL'
        - CommandLine|contains|all:
              - 'url.dll'
              - 'OpenURL'
        - CommandLine|contains|all:
              - 'url.dll'
              - 'OpenURLA'
        - CommandLine|contains|all:
              - 'url.dll'
              - 'FileProtocolHandler'
        - CommandLine|contains|all:
              - 'zipfldr.dll'
              - 'RouteTheCall'
        - CommandLine|contains|all:
              - 'shell32.dll'
              - 'Control_RunDLL'
        - CommandLine|contains|all:
              - 'shell32.dll'
              - 'ShellExec_RunDLL'
        - CommandLine|contains|all:
              - 'mshtml.dll'
              - 'PrintHTML'
        - CommandLine|contains|all:
              - 'advpack.dll'
              - 'LaunchINFSection'
        - CommandLine|contains|all:
              - 'advpack.dll'
              - 'RegisterOCX'
        - CommandLine|contains|all:
              - 'ieadvpack.dll'
              - 'LaunchINFSection'
        - CommandLine|contains|all:
              - 'ieadvpack.dll'
              - 'RegisterOCX'
        - CommandLine|contains|all:
              - 'ieframe.dll'
              - 'OpenURL'
        - CommandLine|contains|all:
              - 'shdocvw.dll'
              - 'OpenURL'
        - CommandLine|contains|all:
              - 'syssetup.dll'
              - 'SetupInfObjectInstallAction'
        - CommandLine|contains|all:
              - 'setupapi.dll'
              - 'InstallHinfSection'
        - CommandLine|contains|all:
              - 'pcwutl.dll'
              - 'LaunchApplication'
        - CommandLine|contains|all:
              - 'dfshim.dll'
              - 'ShOpenVerbApplication'
        - CommandLine|contains|all:
              - 'dfshim.dll'
              - 'ShOpenVerbShortcut'
        - CommandLine|contains|all:
              - 'scrobj.dll'
              - 'GenerateTypeLib'
              - 'http'
        - CommandLine|contains|all:
              - 'shimgvw.dll'
              - 'ImageView_Fullscreen'
              - 'http'
        - CommandLine|contains|all:
              - 'comsvcs.dll'
              - 'MiniDump'
    filter_main_screensaver:
        CommandLine|contains: 'shell32.dll,Control_RunDLL desk.cpl,screensaver,@screensaver'
    filter_main_parent_cpl:  # Settings
        ParentImage: 'C:\Windows\System32\control.exe'
        ParentCommandLine|contains: '.cpl'
        CommandLine|contains|all:
            - 'Shell32.dll'
            - 'Control_RunDLL'
            - '.cpl'
    filter_main_startmenu:
        ParentImage: 'C:\Windows\System32\control.exe'
        CommandLine|startswith: '"C:\Windows\system32\rundll32.exe" Shell32.dll,Control_RunDLL "C:\Windows\System32\'
        CommandLine|endswith: '.cpl",'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - False positives depend on scripts and administrative tools used in the monitored environment
level: medium
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_rundll32_susp_activity/info.yml

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_*

Stage 1: selection

selection:
    - CommandLine|contains|all:
          - 'javascript:'
          - '.RegisterXLL'
    - CommandLine|contains|all:
          - 'url.dll'
          - 'OpenURL'
    - CommandLine|contains|all:
          - 'url.dll'
          - 'OpenURLA'
    - CommandLine|contains|all:
          - 'url.dll'
          - 'FileProtocolHandler'
    - CommandLine|contains|all:
          - 'zipfldr.dll'
          - 'RouteTheCall'
    - CommandLine|contains|all:
          - 'shell32.dll'
          - 'Control_RunDLL'
    - CommandLine|contains|all:
          - 'shell32.dll'
          - 'ShellExec_RunDLL'
    - CommandLine|contains|all:
          - 'mshtml.dll'
          - 'PrintHTML'
    - CommandLine|contains|all:
          - 'advpack.dll'
          - 'LaunchINFSection'
    - CommandLine|contains|all:
          - 'advpack.dll'
          - 'RegisterOCX'
    - CommandLine|contains|all:
          - 'ieadvpack.dll'
          - 'LaunchINFSection'
    - CommandLine|contains|all:
          - 'ieadvpack.dll'
          - 'RegisterOCX'
    - CommandLine|contains|all:
          - 'ieframe.dll'
          - 'OpenURL'
    - CommandLine|contains|all:
          - 'shdocvw.dll'
          - 'OpenURL'
    - CommandLine|contains|all:
          - 'syssetup.dll'
          - 'SetupInfObjectInstallAction'
    - CommandLine|contains|all:
          - 'setupapi.dll'
          - 'InstallHinfSection'
    - CommandLine|contains|all:
          - 'pcwutl.dll'
          - 'LaunchApplication'
    - CommandLine|contains|all:
          - 'dfshim.dll'
          - 'ShOpenVerbApplication'
    - CommandLine|contains|all:
          - 'dfshim.dll'
          - 'ShOpenVerbShortcut'
    - CommandLine|contains|all:
          - 'scrobj.dll'
          - 'GenerateTypeLib'
          - 'http'
    - CommandLine|contains|all:
          - 'shimgvw.dll'
          - 'ImageView_Fullscreen'
          - 'http'
    - CommandLine|contains|all:
          - 'comsvcs.dll'
          - 'MiniDump'

Stage 2: not filter_main_*

filter_main_screensaver:
    CommandLine|contains: 'shell32.dll,Control_RunDLL desk.cpl,screensaver,@screensaver'
filter_main_parent_cpl:
    ParentImage: 'C:\Windows\System32\control.exe'
    ParentCommandLine|contains: '.cpl'
    CommandLine|contains|all:
        - 'Shell32.dll'
        - 'Control_RunDLL'
        - '.cpl'
filter_main_startmenu:
    ParentImage: 'C:\Windows\System32\control.exe'
    CommandLine|startswith: '"C:\Windows\system32\rundll32.exe" Shell32.dll,Control_RunDLL "C:\Windows\System32\'
    CommandLine|endswith: '.cpl",'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • .RegisterXLL
  • Control_RunDLL corpus 6 (sigma 3, splunk 2, elastic 1)
  • FileProtocolHandler
  • GenerateTypeLib
  • ImageView_Fullscreen
  • InstallHinfSection
  • LaunchApplication corpus 2 (sigma 2)
  • LaunchINFSection
  • MiniDump corpus 4 (sigma 4)
  • OpenURL
  • OpenURLA
  • PrintHTML
  • RegisterOCX
  • RouteTheCall
  • SetupInfObjectInstallAction
  • ShOpenVerbApplication
  • ShOpenVerbShortcut
  • ShellExec_RunDLL corpus 3 (sigma 3)
  • advpack.dll
  • comsvcs.dll corpus 3 (sigma 2, splunk 1)
  • dfshim.dll
  • http corpus 45 (sigma 34, elastic 10, splunk 1)
  • ieadvpack.dll
  • ieframe.dll
  • javascript:
  • mshtml.dll
  • pcwutl.dll
  • scrobj.dll corpus 2 (sigma 1, elastic 1)
  • setupapi.dll
  • shdocvw.dll
  • shell32.dll corpus 3 (sigma 3)
  • shimgvw.dll
  • syssetup.dll
  • url.dll
  • zipfldr.dll
field:"CommandLine" kind:match

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
CommandLineends_with.cpl",excludes:CommandLine
CommandLinestarts_with"C:\Windows\system32\rundll32.exe" Shell32.dll,Control_RunDLL "C:\Windows\System32\excludes:CommandLine
ParentImageeqC:\Windows\System32\control.exeexcludes:ParentImage field:"ParentImage" value:"C:\Windows\System32\control.exe"
CommandLinematch.cplexcludes:CommandLine field:"CommandLine" value:".cpl"
CommandLinematchControl_RunDLLexcludes:CommandLine field:"CommandLine" value:"Control_RunDLL"
CommandLinematchShell32.dllexcludes:CommandLine field:"CommandLine" value:"Shell32.dll"
ParentCommandLinematch.cplexcludes:ParentCommandLine field:"ParentCommandLine" value:".cpl"
CommandLinematchshell32.dll,Control_RunDLL desk.cpl,screensaver,@screensaverexcludes:CommandLine field:"CommandLine" value:"shell32.dll,Control_RunDLL desk.cpl,screensaver,@screensaver"

PUA - NPS Tunneling Tool Execution

#
Status
test
Severity
high
Author
Florian Roth (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects the use of NPS, a port forwarding and intranet penetration proxy server

Known False Positives

  • Legitimate use

MITRE ATT&CK Coverage

TacticTechniques
Command & Control

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: PUA - NPS Tunneling Tool Execution
id: 68d37776-61db-42f5-bf54-27e87072d17e
status: test
description: Detects the use of NPS, a port forwarding and intranet penetration proxy server
references:
    - https://github.com/ehang-io/nps
author: Florian Roth (Nextron Systems)
date: 2022-10-08
modified: 2024-11-23
tags:
    - attack.command-and-control
    - attack.t1090
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        Image|endswith: '\npc.exe'
    selection_cli_1:
        CommandLine|contains|all:
            - ' -server='
            - ' -vkey='
            - ' -password='
    selection_cli_2:
        CommandLine|contains: ' -config=npc'
    selection_hashes:
        # v0.26.10
        Hashes|contains:
            - "MD5=AE8ACF66BFE3A44148964048B826D005"
            - "SHA1=CEA49E9B9B67F3A13AD0BE1C2655293EA3C18181"
            - "SHA256=5A456283392FFCEEEACA3D3426C306EB470304637520D72FED1CC1FEBBBD6856"
    condition: 1 of selection_*
falsepositives:
    - Legitimate use
level: high

Stages and Predicates

Stage 0: condition

1 of selection_*

Stage 1: selection_img

selection_img:
    Image|endswith: '\npc.exe'

Stage 2: selection_cli_1

selection_cli_1:
    CommandLine|contains|all:
        - ' -server='
        - ' -vkey='
        - ' -password='

Stage 3: selection_cli_2

selection_cli_2:
    CommandLine|contains: ' -config=npc'

Stage 4: selection_hashes

selection_hashes:
    Hashes|contains:
        - "MD5=AE8ACF66BFE3A44148964048B826D005"
        - "SHA1=CEA49E9B9B67F3A13AD0BE1C2655293EA3C18181"
        - "SHA256=5A456283392FFCEEEACA3D3426C306EB470304637520D72FED1CC1FEBBBD6856"

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • -config=npc
  • -password=
  • -server=
  • -vkey=
field:"CommandLine" kind:match
Hashesmatch
  • MD5=AE8ACF66BFE3A44148964048B826D005
  • SHA1=CEA49E9B9B67F3A13AD0BE1C2655293EA3C18181
  • SHA256=5A456283392FFCEEEACA3D3426C306EB470304637520D72FED1CC1FEBBBD6856
field:"Hashes" kind:match
Imageends_with
  • \npc.exe
field:"Image" kind:ends_with value:"\npc.exe"

Remove Exported Mailbox from Exchange Webserver

#
Status
test
Severity
high
Author
Christian Burkard (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects removal of an exported Exchange mailbox which could be to cover tracks from ProxyShell exploit

MITRE ATT&CK Coverage

TacticTechniques
Stealth

Rule Body

title: Remove Exported Mailbox from Exchange Webserver
id: 09570ae5-889e-43ea-aac0-0e1221fb3d95
status: test
description: Detects removal of an exported Exchange mailbox which could be to cover tracks from ProxyShell exploit
references:
    - https://github.com/rapid7/metasploit-framework/blob/1416b5776d963f21b7b5b45d19f3e961201e0aed/modules/exploits/windows/http/exchange_proxyshell_rce.rb#L430
author: Christian Burkard (Nextron Systems)
date: 2021-08-27
modified: 2023-01-23
tags:
    - attack.stealth
    - attack.t1070
logsource:
    service: msexchange-management
    product: windows
detection:
    keywords:
        '|all':
            - 'Remove-MailboxExportRequest'
            - ' -Identity '
            - ' -Confirm "False"'
    condition: keywords
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

keywords

Stage 1: keywords

keywords:
    '|all':
        - 'Remove-MailboxExportRequest'
        - ' -Identity '
        - ' -Confirm "False"'

SAM database user credentials dump with Mimikatz

#
Status
experimental
Severity
high
Author
mdecrevoisier
Source
github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker dump the LSASS memory content using Mimikatz (sekurlsa module).

Known False Positives

  • None

MITRE ATT&CK Coverage

TacticTechniques
Credential Access

Telemetry Coverage

Rule Body

title: SAM database user credentials dump with Mimikatz
description: Detects scenarios where an attacker dump the LSASS memory content using Mimikatz (sekurlsa module).
correlation: correlate TargetLogonId from ID 4624 with SubjectLogonId from ID 4661 to identify the source of the enumeration.
requirements: extended rights auditing enabled (https://www.manageengine.com/products/active-directory-audit/active-directory-auditing-configuration-guide-configure-object-level-auditing-manually.html)
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0006-Credential%20Access/T1003-Credential%20dumping
- https://ivanitlearning.wordpress.com/2019/09/07/mimikatz-and-password-dumps/
tags:
- attack.credential_access
- attack.t1003.001
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  service: security
detection:
  selection:
    EventID: 4661
    ProcessName|endswith: '\lsass.exe'
    ObjectServer: Security Account Manager
    ObjectType: SAM_USER
    ObjectName|startswith: 'S-1-5-21-' # User SID dumped
    AccessList|contains|all:
      - '%%5446' # ChangePassword
      - '%%5447' # SetPassword
  filter:
    SubjectUserName|endswith: '$'
  condition: selection and not filter | count(ObjectName) by Computer > 10
falsepositives:
- None
level: high

Stages and Predicates

Stage 0: condition

selection and not filter | count(ObjectName) by Computer > 10

Stage 1: selection

selection:
  EventID: 4661
  ProcessName|endswith: '\lsass.exe'
  ObjectServer: Security Account Manager
  ObjectType: SAM_USER
  ObjectName|startswith: 'S-1-5-21-'
  AccessList|contains|all:
    - '%%5446'
    - '%%5447'
Threshold
> 10

Stage 2: not filter

filter:
  SubjectUserName|endswith: '$'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
AccessListmatch
  • %%5446
  • %%5447 corpus 2 (sigma 2)
field:"AccessList" kind:match
ObjectNamestarts_with
  • S-1-5-21- corpus 5 (sigma 5)
field:"ObjectName" kind:starts_with value:"S-1-5-21-"
ObjectServereq
  • Security Account Manager corpus 7 (sigma 7)
field:"ObjectServer" kind:eq value:"Security Account Manager"
ObjectTypeeq
  • SAM_USER corpus 5 (sigma 5)
field:"ObjectType" kind:eq value:"SAM_USER"
ProcessNameends_with
  • \lsass.exe corpus 7 (sigma 7)
field:"process_name" kind:ends_with value:"\lsass.exe"

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
SubjectUserNameends_with$excludes:SubjectUserName field:"SubjectUserName" value:"$"

SQL Server xp_cmdshell activation (native event)

#
Status
experimental
Severity
high
Author
mdecrevoisier
Source
github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker enable the xp_cmdshell in order to execute non SQL content and escalate privileges

Known False Positives

  • None

MITRE ATT&CK Coverage

TacticTechniques
Persistence

Telemetry Coverage

ProviderRecord / event type
MSSQLSERVEREvent ID 15457

Rule Body

title: SQL Server xp_cmdshell activation (native event)
description: Detects scenarios where an attacker enable the xp_cmdshell in order to execute non SQL content and escalate privileges
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0003-Persistence/T1505.001-SQL%20Stored%20Procedures
- https://thedfirreport.com/2022/07/11/select-xmrig-from-sqlserver/
- https://asec.ahnlab.com/en/52479/
- https://www.microsoft.com/en-us/security/blog/2023/10/03/defending-new-vectors-threat-actors-attempt-sql-server-to-cloud-lateral-movement/
- https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure%20SQL%20Database%20solution%20for%20sentinel/Hunting%20Queries/HuntingQuery-SuspiciousStoredProcedures.yaml
tags:
- attack.persistence
- attack.T1505
author: mdecrevoisier
status: experimental
logsource:
  product: mssql
  category: application
detection:
  selection_baseline:
    EventID: 15457

  selection_raw: # Safest approach, not localized and not dependent on system and application language
    EventData|contains: '<Data>xp_cmdshell</Data><Data>0</Data><Data>1</Data>' # 0 is for previous status and 1 for new status

  selection_enriched: # Alternative method using Message. However this field may be in a different language and dropped in some cases during collection phase
    Message|contains: "option 'xp_cmdshell' changed from 0 to 1"

  condition: selection_baseline and (selection_raw or selection_enriched)
falsepositives:
- None
level: high

Stages and Predicates

Stage 0: condition

selection_baseline and (selection_raw or selection_enriched)

Stage 1: selection_baseline

selection_baseline:
  EventID: 15457

Stage 2: selection_raw

selection_raw:
  EventData|contains: '<Data>xp_cmdshell</Data><Data>0</Data><Data>1</Data>'

Stage 3: selection_enriched

selection_enriched:
  Message|contains: "option 'xp_cmdshell' changed from 0 to 1"

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
EventDatamatch
  • <Data>xp_cmdshell</Data><Data>0</Data><Data>1</Data>
field:"EventData" kind:match value:"<Data>xp_cmdshell</Data><Data>0</Data><Data>1</Data>"
Messagematch
  • option 'xp_cmdshell' changed from 0 to 1
field:"Message" kind:match value:"option 'xp_cmdshell' changed from 0 to 1"

Stop Windows Service Via Net.EXE

#
Status
test
Severity
low
Author
Jakob Weinzettl, oscd.community, Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects the stopping of a Windows service via the "net" utility.

Known False Positives

  • There are many legitimate reasons to stop a service. This rule isn't looking for any suspicious behaviour in particular. Filter legitimate activity accordingly

MITRE ATT&CK Coverage

TacticTechniques
Impact

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: Stop Windows Service Via Net.EXE
id: 88872991-7445-4a22-90b2-a3adadb0e827
related:
    - id: eb87818d-db5d-49cc-a987-d5da331fbd90
      type: obsolete
status: test
description: Detects the stopping of a Windows service via the "net" utility.
references:
    - https://ss64.com/nt/net-service.html
author: Jakob Weinzettl, oscd.community, Nasreddine Bencherchali (Nextron Systems)
date: 2023-03-05
tags:
    - attack.impact
    - attack.t1489
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - OriginalFileName:
              - 'net.exe'
              - 'net1.exe'
        - Image|endswith:
              - '\net.exe'
              - '\net1.exe'
    selection_cli:
        CommandLine|contains: ' stop '
    condition: all of selection_*
falsepositives:
    - There are many legitimate reasons to stop a service. This rule isn't looking for any suspicious behaviour in particular. Filter legitimate activity accordingly
level: low

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_img

selection_img:
    - OriginalFileName:
          - 'net.exe'
          - 'net1.exe'
    - Image|endswith:
          - '\net.exe'
          - '\net1.exe'

Stage 2: selection_cli

selection_cli:
    CommandLine|contains: ' stop '

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • stop corpus 8 (sigma 6, splunk 2)
field:"CommandLine" kind:match value:" stop "
Imageends_with
  • \net.exe corpus 49 (sigma 49)
  • \net1.exe corpus 47 (sigma 47)
field:"Image" kind:ends_with
OriginalFileNameeq
  • net.exe corpus 25 (sigma 19, elastic 4, splunk 2)
  • net1.exe corpus 39 (sigma 19, splunk 19, elastic 1)
field:"OriginalFileName" kind:eq

Suspicious Execution of Systeminfo

#
Status
test
Severity
low
Author
frack113
Source
github.com/SigmaHQ/sigma

Detects usage of the "systeminfo" command to retrieve information

MITRE ATT&CK Coverage

TacticTechniques
Discovery

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: Suspicious Execution of Systeminfo
id: 0ef56343-059e-4cb6-adc1-4c3c967c5e46
status: test
description: Detects usage of the "systeminfo" command to retrieve information
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1082/T1082.md#atomic-test-1---system-information-discovery
    - https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/systeminfo
author: frack113
date: 2022-01-01
modified: 2022-07-14
tags:
    - attack.discovery
    - attack.t1082
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        - Image|endswith: '\systeminfo.exe'
        - OriginalFileName: 'sysinfo.exe'
    condition: selection
falsepositives:
    - Unknown
level: low

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    - Image|endswith: '\systeminfo.exe'
    - OriginalFileName: 'sysinfo.exe'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \systeminfo.exe corpus 11 (sigma 11)
field:"Image" kind:ends_with value:"\systeminfo.exe"
OriginalFileNameeq
  • sysinfo.exe corpus 2 (sigma 2)
field:"OriginalFileName" kind:eq value:"sysinfo.exe"

Suspicious Get-Variable.exe Creation

#
Status
test
Severity
high
Author
frack113
Source
github.com/SigmaHQ/sigma

Get-Variable is a valid PowerShell cmdlet WindowsApps is by default in the path where PowerShell is executed. So when the Get-Variable command is issued on PowerShell execution, the system first looks for the Get-Variable executable in the path and executes the malicious binary instead of looking for the PowerShell cmdlet.

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 11: FileCreate

Rule Body

title: Suspicious Get-Variable.exe Creation
id: 0c3fac91-5627-46e8-a6a8-a0d7b9b8ae1b
status: test
description: |
    Get-Variable is a valid PowerShell cmdlet
    WindowsApps is by default in the path where PowerShell is executed.
    So when the Get-Variable command is issued on PowerShell execution, the system first looks for the Get-Variable executable in the path and executes the malicious binary instead of looking for the PowerShell cmdlet.
references:
    - https://blog.malwarebytes.com/threat-intelligence/2022/04/colibri-loader-combines-task-scheduler-and-powershell-in-clever-persistence-technique/
    - https://www.joesandbox.com/analysis/465533/0/html
author: frack113
date: 2022-04-23
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.stealth
    - attack.t1546
    - attack.t1027
logsource:
    product: windows
    category: file_event
detection:
    selection:
        TargetFilename|endswith: 'Local\Microsoft\WindowsApps\Get-Variable.exe'
    condition: selection
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    TargetFilename|endswith: 'Local\Microsoft\WindowsApps\Get-Variable.exe'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
TargetFilenameends_with
  • Local\Microsoft\WindowsApps\Get-Variable.exe
field:"TargetFilename" kind:ends_with value:"Local\Microsoft\WindowsApps\Get-Variable.exe"

Suspicious Scheduled Task Write to System32 Tasks

#
Status
test
Severity
high
Author
Florian Roth (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects the creation of tasks from processes executed from suspicious locations

MITRE ATT&CK Coverage

TacticTechniques
Execution
Persistence
Privilege Escalation

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 11: FileCreate

Rule Body

title: Suspicious Scheduled Task Write to System32 Tasks
id: 80e1f67a-4596-4351-98f5-a9c3efabac95
status: test
description: Detects the creation of tasks from processes executed from suspicious locations
references:
    - Internal Research
author: Florian Roth (Nextron Systems)
date: 2021-11-16
modified: 2022-01-12
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.execution
    - attack.t1053
logsource:
    product: windows
    category: file_event
detection:
    selection:
        TargetFilename|contains: '\Windows\System32\Tasks'
        Image|contains:
            - '\AppData\'
            - 'C:\PerfLogs'
            - '\Windows\System32\config\systemprofile'
    condition: selection
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    TargetFilename|contains: '\Windows\System32\Tasks'
    Image|contains:
        - '\AppData\'
        - 'C:\PerfLogs'
        - '\Windows\System32\config\systemprofile'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imagematch
  • C:\PerfLogs
  • \AppData\ corpus 6 (sigma 6)
  • \Windows\System32\config\systemprofile
field:"Image" kind:match
TargetFilenamematch
  • \Windows\System32\Tasks
field:"TargetFilename" kind:match value:"\Windows\System32\Tasks"

Suspicious Screensaver Binary File Creation

#
Status
test
Severity
medium
Author
frack113
Source
github.com/SigmaHQ/sigma

Adversaries may establish persistence by executing malicious content triggered by user inactivity. Screensavers are programs that execute after a configurable time of user inactivity and consist of Portable Executable (PE) files with a .scr file extension

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 11: FileCreate

Rule Body

title: Suspicious Screensaver Binary File Creation
id: 97aa2e88-555c-450d-85a6-229bcd87efb8
status: test
description: |
    Adversaries may establish persistence by executing malicious content triggered by user inactivity.
    Screensavers are programs that execute after a configurable time of user inactivity and consist of Portable Executable (PE) files with a .scr file extension
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1546.002/T1546.002.md
author: frack113
date: 2021-12-29
modified: 2022-11-08
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.t1546.002
logsource:
    product: windows
    category: file_event
detection:
    selection:
        TargetFilename|endswith: '.scr'
    filter_generic:
        Image|endswith:
            - '\Kindle.exe'
            - '\Bin\ccSvcHst.exe' # Symantec Endpoint Protection
    filter_tiworker:
        # ParentCommandLine: C:\WINDOWS\system32\svchost.exe -k DcomLaunch -p
        Image|endswith: '\TiWorker.exe'
        TargetFilename|endswith: '\uwfservicingscr.scr'
    condition: selection and not 1 of filter_*
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_*

Stage 1: selection

selection:
    TargetFilename|endswith: '.scr'

Stage 2: not filter_*

filter_generic:
    Image|endswith:
        - '\Kindle.exe'
        - '\Bin\ccSvcHst.exe'
filter_tiworker:
    Image|endswith: '\TiWorker.exe'
    TargetFilename|endswith: '\uwfservicingscr.scr'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
TargetFilenameends_with
  • .scr corpus 8 (sigma 8)
field:"TargetFilename" kind:ends_with value:".scr"

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
Imageends_with\TiWorker.exeexcludes:Image field:"Image" value:"\TiWorker.exe"
TargetFilenameends_with\uwfservicingscr.screxcludes:TargetFilename field:"TargetFilename" value:"\uwfservicingscr.scr"
Imageends_with\Bin\ccSvcHst.exeexcludes:Image field:"Image" value:"\Bin\ccSvcHst.exe"
Imageends_with\Kindle.exeexcludes:Image field:"Image" value:"\Kindle.exe"

Sysinternals PsSuspend Execution

#
Status
test
Severity
medium
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects usage of Sysinternals PsSuspend which can be abused to suspend critical processes

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: Sysinternals PsSuspend Execution
id: 48bbc537-b652-4b4e-bd1d-281172df448f
related:
    - id: 4beb6ae0-f85b-41e2-8f18-8668abc8af78
      type: similar
status: test
description: Detects usage of Sysinternals PsSuspend which can be abused to suspend critical processes
references:
    - https://learn.microsoft.com/en-us/sysinternals/downloads/pssuspend
    - https://twitter.com/0gtweet/status/1638069413717975046
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-03-23
modified: 2026-06-29
tags:
    - attack.privilege-escalation
    - attack.discovery
    - attack.persistence
    - attack.t1543.003
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        - OriginalFileName: 'pssuspend.exe'
        - Image|endswith:
              - '\pssuspend.exe'
              - '\pssuspend64.exe'
              - '\pssuspend64a.exe'
    condition: selection
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    - OriginalFileName: 'pssuspend.exe'
    - Image|endswith:
          - '\pssuspend.exe'
          - '\pssuspend64.exe'
          - '\pssuspend64a.exe'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \pssuspend.exe corpus 3 (sigma 3)
  • \pssuspend64.exe corpus 3 (sigma 3)
  • \pssuspend64a.exe corpus 3 (sigma 3)
field:"Image" kind:ends_with
OriginalFileNameeq
  • pssuspend.exe corpus 2 (sigma 2)
field:"OriginalFileName" kind:eq value:"pssuspend.exe"

Triple Cross eBPF Rootkit Default LockFile

#
Status
test
Severity
high
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects the creation of the file "rootlog" which is used by the TripleCross rootkit as a way to check if the backdoor is already running.

Known False Positives

  • Unlikely

MITRE ATT&CK Coverage

TacticTechniques
StealthNo specific technique

Telemetry Coverage

PlatformRecord / event type
LinuxEvent ID 11: File created

Rule Body

title: Triple Cross eBPF Rootkit Default LockFile
id: c0239255-822c-4630-b7f1-35362bcb8f44
status: test
description: Detects the creation of the file "rootlog" which is used by the TripleCross rootkit as a way to check if the backdoor is already running.
references:
    - https://github.com/h3xduck/TripleCross/blob/1f1c3e0958af8ad9f6ebe10ab442e75de33e91de/src/helpers/execve_hijack.c#L33
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-07-05
modified: 2022-12-31
tags:
    - attack.stealth
logsource:
    product: linux
    category: file_event
detection:
    selection:
        TargetFilename: '/tmp/rootlog'
    condition: selection
falsepositives:
    - Unlikely
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    TargetFilename: '/tmp/rootlog'

Indicators

These rows show field, operator, and value matches.

Unusual Child Process of dns.exe

#
Status
test
Severity
high
Author
Tim Rauch, Elastic (idea)
Source
github.com/SigmaHQ/sigma

Detects an unexpected process spawning from dns.exe which may indicate activity related to remote code execution or other forms of exploitation as seen in CVE-2020-1350 (SigRed)

MITRE ATT&CK Coverage

TacticTechniques
Initial Access
Persistence

Telemetry Coverage

Rule Body

title: Unusual Child Process of dns.exe
id: a4e3d776-f12e-42c2-8510-9e6ed1f43ec3
status: test
description: Detects an unexpected process spawning from dns.exe which may indicate activity related to remote code execution or other forms of exploitation as seen in CVE-2020-1350 (SigRed)
references:
    - https://www.elastic.co/guide/en/security/current/unusual-child-process-of-dns-exe.html
author: Tim Rauch, Elastic (idea)
date: 2022-09-27
modified: 2023-02-05
tags:
    - attack.persistence
    - attack.initial-access
    - attack.t1133
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        ParentImage|endswith: '\dns.exe'
    filter:
        Image|endswith: '\conhost.exe'
    condition: selection and not filter
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection and not filter

Stage 1: selection

selection:
    ParentImage|endswith: '\dns.exe'

Stage 2: not filter

filter:
    Image|endswith: '\conhost.exe'

Indicators

These rows show field, operator, and value matches.

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
Imageends_with\conhost.exeexcludes:Image field:"Image" value:"\conhost.exe"

WMIC Loading Scripting Libraries

#
Status
test
Severity
medium
Author
Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research)
Source
github.com/SigmaHQ/sigma

Detects threat actors proxy executing code and bypassing application controls by leveraging wmic and the /FORMAT argument switch to download and execute an XSL file (i.e js, vbs, etc). It could be an indicator of SquiblyTwo technique, which uses Windows Management Instrumentation (WMI) to execute malicious code.

Known False Positives

  • The command wmic os get lastbootuptime loads vbscript.dll
  • The command wmic os get locale loads vbscript.dll
  • Since the ImageLoad event doesn't have enough information in this case. It's better to look at the recent process creation events that spawned the WMIC process and investigate the command line and parent/child processes to get more insights
  • The command `wmic ntevent` loads vbscript.dll

MITRE ATT&CK Coverage

TacticTechniques
Stealth

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 7: Image loaded

Rule Body

title: WMIC Loading Scripting Libraries
id: 06ce37c2-61ab-4f05-9ff5-b1a96d18ae32
related:
    - id: 8d63dadf-b91b-4187-87b6-34a1114577ea
      type: similar
    - id: 05c36dd6-79d6-4a9a-97da-3db20298ab2d
      type: similar
status: test
description: |
    Detects threat actors proxy executing code and bypassing application controls by leveraging wmic and the `/FORMAT` argument switch to download and execute an XSL file (i.e js, vbs, etc).
    It could be an indicator of SquiblyTwo technique, which uses Windows Management Instrumentation (WMI) to execute malicious code.
references:
    - https://securitydatasets.com/notebooks/atomic/windows/defense_evasion/SDWIN-201017061100.html
    - https://twitter.com/dez_/status/986614411711442944
    - https://lolbas-project.github.io/lolbas/Binaries/Wmic/
author: Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research)
date: 2020-10-17
modified: 2022-10-13
tags:
    - attack.stealth
    - attack.t1220
logsource:
    category: image_load
    product: windows
detection:
    selection:
        Image|endswith: '\wmic.exe'
        ImageLoaded|endswith:
            - '\jscript.dll'
            - '\vbscript.dll'
    condition: selection
falsepositives:
    - The command wmic os get lastbootuptime loads vbscript.dll
    - The command wmic os get locale loads vbscript.dll
    - Since the ImageLoad event doesn't have enough information in this case. It's better to look at the recent process creation events that spawned the WMIC process and investigate the command line and parent/child processes to get more insights
    - The command `wmic ntevent` loads vbscript.dll
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith: '\wmic.exe'
    ImageLoaded|endswith:
        - '\jscript.dll'
        - '\vbscript.dll'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \wmic.exe corpus 62 (sigma 62)
field:"Image" kind:ends_with value:"\wmic.exe"
ImageLoadedends_with
  • \jscript.dll corpus 2 (sigma 2)
  • \vbscript.dll corpus 3 (sigma 3)
field:"ImageLoaded" kind:ends_with

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