Detection rules › Sigma

Sigma rules: 35

RuleSeverity
Account password set to never expire.medium
Account set with Kerberos pre-authentication not required (AS-REP Roasting)high
Arbitrary Command Execution Using WSLmedium
Arbitrary MSI Download Via Devinit.EXEmedium
Bypass UAC via WSReset.exehigh
Diamond Sleet APT File Creation Indicatorshigh
DNS HybridConnectionManager Service Bushigh
HackTool - CobaltStrike Malleable Profile Patterns - Proxyhigh
Inbox Rules Creation Or Update Activity in O365medium
Kapeka Backdoor Loaded Via Rundll32.EXEhigh
Lazarus System Binary Masqueradinghigh
Logging Configuration Changes on Linux Hosthigh
Microsoft VBA For Outlook Addin Loaded Via Outlookmedium
MSHTA Execution with Suspicious File Extensionshigh
Network Connection Initiated From Users\Public Foldermedium
OpenCanary - SNMP OID Requesthigh
Password Policy Discovery - Linuxlow
Potential CVE-2022-21587 Exploitation Attempthigh
Potential SSH Tunnel Persistence Install Using A Scheduled Taskhigh
Potential Startup Shortcut Persistence Via PowerShell.EXEhigh
Potential Tampering With RDP Related Registry Keys Via Reg.EXEhigh
PUA - Netcat Suspicious Executionhigh
PUA - NimScan Executionmedium
Service Started/Stopped Via Wmic.EXEmedium
Solarwinds SUPERNOVA Webshell Accesscritical
Suspicious Execution of Shutdown to Log Outmedium
Suspicious modification of a user account SPN to enable Kerberoast attackhigh
System Integrity Protection (SIP) Enumerationlow
TropicTrooper Campaign November 2018high
Unsigned Binary Loaded From Suspicious Locationhigh
Windows Firewall Settings Have Been Changedlow

Account password set to never expire.

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

Detects scenarios where an account password is set to never expire.

Known False Positives

  • IAM solution, User Management solutions

MITRE ATT&CK Coverage

TacticTechniques
Persistence

Telemetry Coverage

Rule Body

title: Account password set to never expire.
description: Detects scenarios where an account password is set to never expire.
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0003-Persistence/T1098.xxx-Account%20manipulation
tags:
- attack.persistence
- attack.t1098
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  service: security
detection:
  selection:
    EventID: 4738
    UserAccountControl: '%%2089' # Account never expires - TRUE
  condition: selection
falsepositives:
- IAM solution, User Management solutions
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
  EventID: 4738
  UserAccountControl: '%%2089'

Indicators

These rows show field, operator, and value matches.

Account set with Kerberos pre-authentication not required (AS-REP Roasting)

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

Detects scenarios where an attacker set an account with Kerberos pre-authentication not required to perform offline brutforce. Account with this status can be checked with the following command > "Get-ADUser -Filter 'useraccountcontrol -band 4194304' -Properties useraccountcontrol".

Known False Positives

  • None

MITRE ATT&CK Coverage

TacticTechniques
Persistence

Telemetry Coverage

Rule Body

title: Account set with Kerberos pre-authentication not required (AS-REP Roasting)
description: Detects scenarios where an attacker set an account with Kerberos pre-authentication not required to perform offline brutforce. Account with this status can be checked with the following command > "Get-ADUser -Filter 'useraccountcontrol -band 4194304' -Properties useraccountcontrol".
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0003-Persistence/T1098.xxx-Account%20manipulation
- https://social.technet.microsoft.com/wiki/contents/articles/23559.kerberos-pre-authentication-why-it-should-not-be-disabled.aspx
- https://docs.microsoft.com/en-us/services-hub/health/remediation-steps-ad/remove-the-highly-insecure-des-encryption-from-user-accounts
tags:
- attack.persistence
- attack.t1098
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  service: security
detection:
  selection:
    EventID: 4738
    UserAccountControl: '%%2096' # Do not require Kerberos preauthentication - TRUE
  condition: selection
falsepositives:
- None
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
  EventID: 4738
  UserAccountControl: '%%2096'

Indicators

These rows show field, operator, and value matches.

Arbitrary Command Execution Using WSL

#
Status
test
Severity
medium
Author
oscd.community, Zach Stanford @svch0st, Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects potential abuse of Windows Subsystem for Linux (WSL) binary as a Living of the Land binary in order to execute arbitrary Linux or Windows commands.

Known False Positives

  • Automation and orchestration scripts may use this method to execute scripts etc.
  • Legitimate use by Windows to kill processes opened via WSL (example VsCode WSL server)

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: Arbitrary Command Execution Using WSL
id: dec44ca7-61ad-493c-bfd7-8819c5faa09b
related:
    - id: 2267fe65-0681-42ad-9a6d-46553d3f3480 # Generic susp child processes rules
      type: similar
status: test
description: |
    Detects potential abuse of Windows Subsystem for Linux (WSL) binary as a Living of the Land binary in order to execute arbitrary Linux or Windows commands.
references:
    - https://lolbas-project.github.io/lolbas/OtherMSBinaries/Wsl/
    - https://twitter.com/nas_bench/status/1535431474429808642
author: oscd.community, Zach Stanford @svch0st, Nasreddine Bencherchali (Nextron Systems)
date: 2020-10-05
modified: 2023-04-12
tags:
    - attack.execution
    - attack.stealth
    - attack.t1218
    - attack.t1202
    - detection.threat-hunting
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\wsl.exe'
        - OriginalFileName: 'wsl.exe'
    selection_cli:
        CommandLine|contains:
            - ' -e '
            - ' --exec'
            - ' --system'
            - ' --shell-type '
            - ' /mnt/c' # Path to mounted "C:\" partition (Indication of running Windows binaries via WSL)
            - ' --user root'
            - ' -u root'
            - '--debug-shell'
    filter_main_kill:
        # This filter is to handle a FP that occurs when a process is spawned from WSL and then closed by the user
        # Example would be to open VsCode through it's server extension from WSL
            # GrandparentCommandLine: "C:\Users\XXX\AppData\Local\Programs\Microsoft VS Code\Code.exe" --ms-enable-electron-run-as-node c:\Users\XXX\.vscode\extensions\ms-vscode-remote.remote-wsl-0.72.0\dist\wslDaemon.js
            # ParentCommandLine: C:\WINDOWS\system32\cmd.exe /d /s /c "C:\WINDOWS\System32\wsl.exe -d Ubuntu-20.04 -e kill 1366"
            # CommandLine: C:\WINDOWS\System32\wsl.exe -d Ubuntu-20.04 -e kill 1366
        ParentImage|endswith: '\cmd.exe'
        CommandLine|contains|all:
            - ' -d '
            - ' -e kill '
    condition: all of selection_* and not 1 of filter_main_*
falsepositives:
    - Automation and orchestration scripts may use this method to execute scripts etc.
    - Legitimate use by Windows to kill processes opened via WSL (example VsCode WSL server)
level: medium

Stages and Predicates

Stage 0: condition

all of selection_* and not 1 of filter_main_*

Stage 1: selection_img

selection_img:
    - Image|endswith: '\wsl.exe'
    - OriginalFileName: 'wsl.exe'

Stage 2: selection_cli

selection_cli:
    CommandLine|contains:
        - ' -e '
        - ' --exec'
        - ' --system'
        - ' --shell-type '
        - ' /mnt/c'
        - ' --user root'
        - ' -u root'
        - '--debug-shell'

Stage 3: not filter_main_kill

filter_main_kill:
    ParentImage|endswith: '\cmd.exe'
    CommandLine|contains|all:
        - ' -d '
        - ' -e kill '

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • --exec
  • --shell-type
  • --system
  • --user root
  • -e corpus 17 (sigma 14, elastic 3)
  • -u root
  • /mnt/c
  • --debug-shell
field:"CommandLine" kind:match
Imageends_with
  • \wsl.exe corpus 11 (sigma 11)
field:"Image" kind:ends_with value:"\wsl.exe"
OriginalFileNameeq
  • wsl.exe
field:"OriginalFileName" kind:eq value:"wsl.exe"

Exclusions

The rule actively suppresses these predicates.

Arbitrary MSI Download Via Devinit.EXE

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

Detects a certain command line flag combination used by "devinit.exe", which can be abused as a LOLBIN to download arbitrary MSI packages on a Windows system

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Arbitrary MSI Download Via Devinit.EXE
id: 90d50722-0483-4065-8e35-57efaadd354d
status: test
description: Detects a certain command line flag combination used by "devinit.exe", which can be abused as a LOLBIN to download arbitrary MSI packages on a Windows system
references:
    - https://twitter.com/mrd0x/status/1460815932402679809
    - https://lolbas-project.github.io/lolbas/OtherMSBinaries/Devinit/
author: Florian Roth (Nextron Systems)
date: 2022-01-11
modified: 2023-04-06
tags:
    - attack.execution
    - attack.stealth
    - attack.t1218
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        CommandLine|contains|all:
            - ' -t msi-install '
            - ' -i http'
    condition: selection
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    CommandLine|contains|all:
        - ' -t msi-install '
        - ' -i http'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • -i http
  • -t msi-install
field:"CommandLine" kind:match

Bypass UAC via WSReset.exe

#
Status
test
Severity
high
Author
E.M. Anhaus (originally from Atomic Blue Detections, Tony Lambert), oscd.community, Florian Roth
Source
github.com/SigmaHQ/sigma

Detects use of WSReset.exe to bypass User Account Control (UAC). Adversaries use this technique to execute privileged processes.

Known False Positives

  • Unknown sub processes of Wsreset.exe

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: Bypass UAC via WSReset.exe
id: d797268e-28a9-49a7-b9a8-2f5039011c5c
related:
    - id: bdc8918e-a1d5-49d1-9db7-ea0fd91aa2ae
      type: obsolete
status: test
description: Detects use of WSReset.exe to bypass User Account Control (UAC). Adversaries use this technique to execute privileged processes.
references:
    - https://eqllib.readthedocs.io/en/latest/analytics/532b5ed4-7930-11e9-8f5c-d46d6d62a49e.html
    - https://lolbas-project.github.io/lolbas/Binaries/Wsreset/
    - https://www.activecyber.us/activelabs/windows-uac-bypass
    - https://twitter.com/ReaQta/status/1222548288731217921
author: E.M. Anhaus (originally from Atomic Blue Detections, Tony Lambert), oscd.community, Florian Roth
date: 2019-10-24
modified: 2022-05-13
tags:
    - attack.privilege-escalation
    - attack.t1548.002
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        ParentImage|endswith: '\wsreset.exe'
    filter:
        - Image|endswith: '\conhost.exe'
        - OriginalFileName: 'CONHOST.EXE'
    condition: selection and not filter
falsepositives:
    - Unknown sub processes of Wsreset.exe
level: high

Stages and Predicates

Stage 0: condition

selection and not filter

Stage 1: selection

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

Stage 2: not filter

filter:
    - Image|endswith: '\conhost.exe'
    - OriginalFileName: '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"
OriginalFileNameeqCONHOST.EXEexcludes:OriginalFileName field:"OriginalFileName" value:"CONHOST.EXE"

Diamond Sleet APT File Creation Indicators

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

Detects file creation activity that is related to Diamond Sleet APT activity

Known False Positives

  • Unlikely

MITRE ATT&CK Coverage

TacticTechniques
ExecutionNo specific technique

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 11: FileCreate

Rule Body

title: Diamond Sleet APT File Creation Indicators
id: e1212b32-55ff-4dfb-a595-62b572248056
status: test
description: Detects file creation activity that is related to Diamond Sleet APT activity
references:
    - https://www.microsoft.com/en-us/security/blog/2023/10/18/multiple-north-korean-threat-actors-exploiting-the-teamcity-cve-2023-42793-vulnerability/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-10-24
tags:
    - attack.execution
    - detection.emerging-threats
logsource:
    category: file_event
    product: windows
detection:
    selection:
        TargetFilename|endswith:
            - ':\ProgramData\4800-84DC-063A6A41C5C'
            - ':\ProgramData\clip.exe'
            - ':\ProgramData\DSROLE.dll'
            - ':\ProgramData\Forest64.exe'
            - ':\ProgramData\readme.md'
            - ':\ProgramData\Version.dll'
            - ':\ProgramData\wsmprovhost.exe'
    condition: selection
falsepositives:
    - Unlikely
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    TargetFilename|endswith:
        - ':\ProgramData\4800-84DC-063A6A41C5C'
        - ':\ProgramData\clip.exe'
        - ':\ProgramData\DSROLE.dll'
        - ':\ProgramData\Forest64.exe'
        - ':\ProgramData\readme.md'
        - ':\ProgramData\Version.dll'
        - ':\ProgramData\wsmprovhost.exe'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
TargetFilenameends_with
  • :\ProgramData\4800-84DC-063A6A41C5C
  • :\ProgramData\DSROLE.dll
  • :\ProgramData\Forest64.exe
  • :\ProgramData\Version.dll
  • :\ProgramData\clip.exe
  • :\ProgramData\readme.md
  • :\ProgramData\wsmprovhost.exe
field:"TargetFilename" kind:ends_with

DNS HybridConnectionManager Service Bus

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

Detects Azure Hybrid Connection Manager services querying the Azure service bus service

Known False Positives

  • Legitimate use of Azure Hybrid Connection Manager and the Azure Service Bus service

MITRE ATT&CK Coverage

TacticTechniques
Persistence

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 22: DNSEvent (DNS query)

Rule Body

title: DNS HybridConnectionManager Service Bus
id: 7bd3902d-8b8b-4dd4-838a-c6862d40150d
status: test
description: Detects Azure Hybrid Connection Manager services querying the Azure service bus service
references:
    - https://twitter.com/Cyb3rWard0g/status/1381642789369286662
author: Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research)
date: 2021-04-12
modified: 2023-01-16
tags:
    - attack.persistence
    - attack.t1554
logsource:
    product: windows
    category: dns_query
detection:
    selection:
        QueryName|contains: 'servicebus.windows.net'
        Image|contains: 'HybridConnectionManager'
    condition: selection
falsepositives:
    - Legitimate use of Azure Hybrid Connection Manager and the Azure Service Bus service
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    QueryName|contains: 'servicebus.windows.net'
    Image|contains: 'HybridConnectionManager'

Indicators

These rows show field, operator, and value matches.

HackTool - CobaltStrike Malleable Profile Patterns - Proxy

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

Detects cobalt strike malleable profiles patterns (URI, User-Agents, Methods).

MITRE ATT&CK Coverage

Rule Body

title: HackTool - CobaltStrike Malleable Profile Patterns - Proxy
id: f3f21ce1-cdef-4bfc-8328-ed2e826f5fac
related:
    - id: 953b895e-5cc9-454b-b183-7f3db555452e
      type: obsolete
    - id: 41b42a36-f62c-4c34-bd40-8cb804a34ad8
      type: obsolete
    - id: 37325383-740a-403d-b1a2-b2b4ab7992e7
      type: obsolete
    - id: c9b33401-cc6a-4cf6-83bb-57ddcb2407fc
      type: obsolete
status: test
description: Detects cobalt strike malleable profiles patterns (URI, User-Agents, Methods).
references:
    - https://github.com/rsmudge/Malleable-C2-Profiles/blob/26323784672913923d20c5a638c6ca79459e8529/normal/amazon.profile
    - https://www.hybrid-analysis.com/sample/ee5eca8648e45e2fea9dac0d920ef1a1792d8690c41ee7f20343de1927cc88b9?environmentId=100
    - https://github.com/rsmudge/Malleable-C2-Profiles/blob/26323784672913923d20c5a638c6ca79459e8529/normal/ocsp.profile
    - https://github.com/yeyintminthuhtut/Malleable-C2-Profiles-Collection/
    - https://github.com/rsmudge/Malleable-C2-Profiles/blob/26323784672913923d20c5a638c6ca79459e8529/normal/onedrive_getonly.profile
author: Markus Neis, Florian Roth (Nextron Systems)
date: 2024-02-15
tags:
    - attack.command-and-control
    - attack.t1071.001
logsource:
    category: proxy
detection:
    selection_amazon_1:
        c-useragent: 'Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko'
        cs-method: 'GET'
        c-uri: '/s/ref=nb_sb_noss_1/167-3294888-0262949/field-keywords=books'
        cs-host: 'www.amazon.com'
        cs-cookie|endswith: '=csm-hit=s-24KU11BB82RZSYGJ3BDK|1419899012996'
    selection_amazon_2:
        c-useragent: 'Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko'
        cs-method: 'POST'
        c-uri: '/N4215/adj/amzn.us.sr.aps'
        cs-host: 'www.amazon.com'
    selection_generic_1:
        c-useragent:
            - 'Mozilla/4.0 (compatible; MSIE 6.0;Windows NT 5.1)'
            - 'Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 3.0.30729; .NET4.0C; .NET4.0E )'
            - 'Mozilla/5.0 (Windows; U; MSIE 7.0; Windows NT 5.2) Java/1.5.0_08'
    selection_generic_2:
        c-useragent|endswith: '; MANM; MANM)'
    selection_oscp:
        c-uri|contains: '/oscp/'
        cs-host: 'ocsp.verisign.com'
    selection_onedrive:
        cs-method: 'GET'
        c-uri|endswith: '\?manifest=wac'
        cs-host: 'onedrive.live.com'
    filter_main_onedrive:
        c-uri|startswith: 'http'
        c-uri|contains: '://onedrive.live.com/'
    condition: 1 of selection_* and not 1 of filter_main_*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

1 of selection_* and not 1 of filter_main_*

Stage 1: selection_amazon_1

selection_amazon_1:
    c-useragent: 'Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko'
    cs-method: 'GET'
    c-uri: '/s/ref=nb_sb_noss_1/167-3294888-0262949/field-keywords=books'
    cs-host: 'www.amazon.com'
    cs-cookie|endswith: '=csm-hit=s-24KU11BB82RZSYGJ3BDK|1419899012996'

Stage 2: selection_amazon_2

selection_amazon_2:
    c-useragent: 'Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko'
    cs-method: 'POST'
    c-uri: '/N4215/adj/amzn.us.sr.aps'
    cs-host: 'www.amazon.com'

Stage 3: selection_generic_1

selection_generic_1:
    c-useragent:
        - 'Mozilla/4.0 (compatible; MSIE 6.0;Windows NT 5.1)'
        - 'Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 3.0.30729; .NET4.0C; .NET4.0E )'
        - 'Mozilla/5.0 (Windows; U; MSIE 7.0; Windows NT 5.2) Java/1.5.0_08'

Stage 4: selection_generic_2

selection_generic_2:
    c-useragent|endswith: '; MANM; MANM)'

Stage 5: selection_oscp

selection_oscp:
    c-uri|contains: '/oscp/'
    cs-host: 'ocsp.verisign.com'

Stage 6: selection_onedrive

selection_onedrive:
    cs-method: 'GET'
    c-uri|endswith: '\?manifest=wac'
    cs-host: 'onedrive.live.com'

Stage 7: not filter_main_onedrive

filter_main_onedrive:
    c-uri|startswith: 'http'
    c-uri|contains: '://onedrive.live.com/'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
c-uriends_with
  • \?manifest=wac
field:"c-uri" kind:ends_with value:"\?manifest=wac"
c-urieq
  • /N4215/adj/amzn.us.sr.aps
  • /s/ref=nb_sb_noss_1/167-3294888-0262949/field-keywords=books
field:"c-uri" kind:eq
c-urimatch
  • /oscp/
field:"c-uri" kind:match value:"/oscp/"
c-useragentends_with
  • ; MANM; MANM)
field:"c-useragent" kind:ends_with value:"; MANM; MANM)"
c-useragenteq
  • Mozilla/4.0 (compatible; MSIE 6.0;Windows NT 5.1)
  • Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 3.0.30729; .NET4.0C; .NET4.0E )
  • Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko
  • Mozilla/5.0 (Windows; U; MSIE 7.0; Windows NT 5.2) Java/1.5.0_08
field:"c-useragent" kind:eq
cs-cookieends_with
  • =csm-hit=s-24KU11BB82RZSYGJ3BDK|1419899012996
field:"cs-cookie" kind:ends_with value:"=csm-hit=s-24KU11BB82RZSYGJ3BDK|1419899012996"
cs-hosteq
  • ocsp.verisign.com
  • onedrive.live.com
  • www.amazon.com
field:"cs-host" kind:eq
cs-methodeq
  • GET
  • POST
field:"cs-method" kind:eq

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
c-urimatch://onedrive.live.com/excludes:c-uri field:"c-uri" value:"://onedrive.live.com/"
c-uristarts_withhttpexcludes:c-uri field:"c-uri" value:"http"

Inbox Rules Creation Or Update Activity in O365

#
Status
experimental
Severity
medium
Author
Marco Pedrinazzi (@pedrinazziM) (InTheCyber)
Source
github.com/SigmaHQ/sigma

Detects inbox rule creation or update via O365 Audit logs, a technique commonly observed in Business Email Compromise (BEC) attacks to hide emails. The usage of inbox rules can be a sign of a compromised mailbox, where an attacker is attempting to evade detections by suppressing or redirecting incoming emails. Analysts should review these rules in context, validate whether they reflect normal user behavior, and correlate with other indicators such as unusual login activity or recent mailbox rule modifications.

Known False Positives

  • Legitimate inbox rules created by users or administrators to manage email flow such as filtering, organizing, or automating email handling.

MITRE ATT&CK Coverage

Telemetry Coverage

Rules Detecting the Same Action

These rules filter on the same operation.

Rule Body

title: Inbox Rules Creation Or Update Activity in O365
id: d3577be1-42c9-44a7-b56e-2e8de97349d3
status: experimental
description: |
    Detects inbox rule creation or update via O365 Audit logs, a technique commonly observed in Business Email Compromise (BEC) attacks to hide emails.
    The usage of inbox rules can be a sign of a compromised mailbox, where an attacker is attempting to evade detections by suppressing or redirecting incoming emails.
    Analysts should review these rules in context, validate whether they reflect normal user behavior, and correlate with other indicators such as unusual login activity or recent mailbox rule modifications.
references:
    - https://redcanary.com/threat-detection-report/techniques/email-hiding-rules/
    - https://learn.microsoft.com/it-it/powershell/module/exchangepowershell/set-inboxrule?view=exchange-ps
    - https://learn.microsoft.com/it-it/powershell/module/exchangepowershell/new-inboxrule?view=exchange-ps
author: Marco Pedrinazzi (@pedrinazziM) (InTheCyber)
date: 2026-01-09
tags:
    - attack.stealth
    - attack.t1564.008
    - attack.exfiltration
    - attack.collection
    - attack.t1114.003
    - detection.threat-hunting
logsource:
    service: audit
    product: m365
    definition: "Requirements: The 'Parameters' field is a list of dict. A correct mapping to the 'Value' field inside is recommended to avoid greedy search"
detection:
    selection:
        Operation:
            - 'New-InboxRule'
            - 'Set-InboxRule'
        Parameters|contains:
            - 'DeleteMessage'
            - 'MarkAsRead'
            - 'MoveToFolder'
            - 'SubjectOrBodyContainsWords'
    condition: selection
falsepositives:
    - Legitimate inbox rules created by users or administrators to manage email flow such as filtering, organizing, or automating email handling.
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Operation:
        - 'New-InboxRule'
        - 'Set-InboxRule'
    Parameters|contains:
        - 'DeleteMessage'
        - 'MarkAsRead'
        - 'MoveToFolder'
        - 'SubjectOrBodyContainsWords'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Operationeq
  • New-InboxRule corpus 5 (splunk 2, kusto 2, sigma 1)
  • Set-InboxRule corpus 3 (splunk 2, sigma 1)
field:"Operation" kind:eq
Parametersmatch
  • DeleteMessage
  • MarkAsRead
  • MoveToFolder
  • SubjectOrBodyContainsWords
field:"m365::Parameters" kind:match

Kapeka Backdoor Loaded Via Rundll32.EXE

#
Status
test
Severity
high
Author
Swachchhanda Shrawan Poudel
Source
github.com/SigmaHQ/sigma

Detects the Kapeka Backdoor binary being loaded by rundll32.exe. The Kapeka loader drops a backdoor, which is a DLL with the '.wll' extension masquerading as a Microsoft Word Add-In.

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 7: Image loaded

Rule Body

title: Kapeka Backdoor Loaded Via Rundll32.EXE
id: a7e6b1f9-8d2c-4f1e-9a7d-63e4c8a2bf4c
status: test
description: |
    Detects the Kapeka Backdoor binary being loaded by rundll32.exe.
    The Kapeka loader drops a backdoor, which is a DLL with the '.wll' extension masquerading as a Microsoft Word Add-In.
references:
    - https://labs.withsecure.com/publications/kapeka
    - https://app.any.run/tasks/1efb3ed4-cc0f-4690-a0ed-24516809bc72/
author: Swachchhanda Shrawan Poudel
date: 2024-07-03
tags:
    - attack.execution
    - attack.stealth
    - attack.t1204.002
    - attack.t1218.011
    - detection.emerging-threats
logsource:
    category: image_load
    product: windows
detection:
    selection:
        Image|endswith: '\rundll32.exe'
        ImageLoaded|contains:
            - ':\ProgramData'
            - '\AppData\Local\'
        ImageLoaded|re: '[a-zA-Z]{5,6}\.wll'
    condition: selection
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith: '\rundll32.exe'
    ImageLoaded|contains:
        - ':\ProgramData'
        - '\AppData\Local\'
    ImageLoaded|re: '[a-zA-Z]{5,6}\.wll'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \rundll32.exe corpus 94 (sigma 94)
field:"Image" kind:ends_with value:"\rundll32.exe"
ImageLoadedmatch
  • :\ProgramData
  • \AppData\Local\
field:"ImageLoaded" kind:match
ImageLoadedregex_match
  • [a-zA-Z]{5,6}.wll
field:"ImageLoaded" kind:regex_match value:"[a-zA-Z]{5,6}.wll"

Lazarus System Binary Masquerading

#
Status
test
Severity
high
Author
Trent Liffick (@tliffick), Bartlomiej Czyz (@bczyz1)
Source
github.com/SigmaHQ/sigma

Detects binaries used by the Lazarus group which use system names but are executed and launched from non-default location

Known False Positives

  • Unlikely

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Lazarus System Binary Masquerading
id: 3f7f5b0b-5b16-476c-a85f-ab477f6dd24b
status: test
description: Detects binaries used by the Lazarus group which use system names but are executed and launched from non-default location
references:
    - https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2018/03/07180244/Lazarus_Under_The_Hood_PDF_final.pdf
author: Trent Liffick (@tliffick), Bartlomiej Czyz (@bczyz1)
date: 2020-06-03
modified: 2023-03-10
tags:
    - attack.stealth
    - attack.t1036.005
    - detection.emerging-threats
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\msdtc.exe'
            - '\gpsvc.exe'
    filter:
        Image|startswith:
            - 'C:\Windows\System32\'
            - 'C:\Windows\SysWOW64\'
    condition: selection and not filter
falsepositives:
    - Unlikely
level: high

Stages and Predicates

Stage 0: condition

selection and not filter

Stage 1: selection

selection:
    Image|endswith:
        - '\msdtc.exe'
        - '\gpsvc.exe'

Stage 2: not filter

filter:
    Image|startswith:
        - 'C:\Windows\System32\'
        - 'C:\Windows\SysWOW64\'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \gpsvc.exe
  • \msdtc.exe corpus 2 (sigma 2)
field:"Image" kind:ends_with

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
Imagestarts_withC:\Windows\SysWOW64\excludes:Image field:"Image" value:"C:\Windows\SysWOW64\"
Imagestarts_withC:\Windows\System32\excludes:Image field:"Image" value:"C:\Windows\System32\"

Logging Configuration Changes on Linux Host

#
Status
test
Severity
high
Author
Mikhail Larin, oscd.community
Source
github.com/SigmaHQ/sigma

Detect changes of syslog daemons configuration files

Known False Positives

  • Legitimate administrative activity

MITRE ATT&CK Coverage

TacticTechniques
Defense Impairment

Telemetry Coverage

Rule Body

title: Logging Configuration Changes on Linux Host
id: c830f15d-6f6e-430f-8074-6f73d6807841
status: test
description: Detect changes of syslog daemons configuration files
references:
    - self experience
author: Mikhail Larin, oscd.community
date: 2019-10-25
modified: 2021-11-27
tags:
    - attack.defense-impairment
    - attack.t1685
logsource:
    product: linux
    service: auditd
detection:
    selection:
        type: 'PATH'
        name:
            - /etc/syslog.conf
            - /etc/rsyslog.conf
            - /etc/syslog-ng/syslog-ng.conf
    condition: selection
falsepositives:
    - Legitimate administrative activity
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    type: 'PATH'
    name:
        - /etc/syslog.conf
        - /etc/rsyslog.conf
        - /etc/syslog-ng/syslog-ng.conf

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
nameeq
  • /etc/rsyslog.conf
  • /etc/syslog-ng/syslog-ng.conf
  • /etc/syslog.conf
field:"name" kind:eq
typeeq
  • PATH corpus 19 (sigma 12, splunk 7)
field:"type" kind:eq value:"PATH"

Microsoft VBA For Outlook Addin Loaded Via Outlook

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

Detects outlvba (Microsoft VBA for Outlook Addin) DLL being loaded by the outlook process

Known False Positives

  • Legitimate macro usage. Add the appropriate filter according to your environment

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 7: Image loaded

Rule Body

title: Microsoft VBA For Outlook Addin Loaded Via Outlook
id: 9a0b8719-cd3c-4f0a-90de-765a4cb3f5ed
status: test
description: Detects outlvba (Microsoft VBA for Outlook Addin) DLL being loaded by the outlook process
references:
    - https://speakerdeck.com/heirhabarov/hunting-for-persistence-via-microsoft-exchange-server-or-outlook?slide=58
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-02-08
modified: 2024-03-12
tags:
    - attack.execution
    - attack.t1204.002
logsource:
    category: image_load
    product: windows
detection:
    selection:
        Image|endswith: '\outlook.exe'
        ImageLoaded|endswith: '\outlvba.dll'
    condition: selection
falsepositives:
    - Legitimate macro usage. Add the appropriate filter according to your environment
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith: '\outlook.exe'
    ImageLoaded|endswith: '\outlvba.dll'

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"
ImageLoadedends_with
  • \outlvba.dll
field:"ImageLoaded" kind:ends_with value:"\outlvba.dll"

MSHTA Execution with Suspicious File Extensions

#
Status
test
Severity
high
Author
Diego Perez (@darkquassar), Markus Neis, Swisscom (Improve Rule), Swachchhanda Shrawan Poudel (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects execution of mshta.exe with file types that looks like they do not typically represent HTA (HTML Application) content, such as .png, .jpg, .zip, .pdf, and others, which are often polyglots. MSHTA is a legitimate Windows utility for executing HTML Applications containing VBScript or JScript. Threat actors often abuse this lolbin utility to download and execute malicious scripts disguised as benign files or hosted under misleading extensions to evade detection.

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: MSHTA Execution with Suspicious File Extensions
id: cc7abbd0-762b-41e3-8a26-57ad50d2eea3
status: test
description: |
    Detects execution of mshta.exe with file types that looks like they do not typically represent HTA (HTML Application) content,
    such as .png, .jpg, .zip, .pdf, and others, which are often polyglots. MSHTA is a legitimate Windows utility for executing HTML Applications
    containing VBScript or JScript. Threat actors often abuse this lolbin utility to download and
    execute malicious scripts disguised as benign files or hosted under misleading extensions to evade detection.
references:
    - http://blog.sevagas.com/?Hacking-around-HTA-files
    - https://0x00sec.org/t/clientside-exploitation-in-2018-how-pentesting-has-changed/7356
    - https://learn.microsoft.com/en-us/previous-versions/dotnet/framework/data/xml/xslt/xslt-stylesheet-scripting-using-msxsl-script
    - https://medium.com/tsscyber/pentesting-and-hta-bypassing-powershell-constrained-language-mode-53a42856c997
    - https://twitter.com/mattifestation/status/1326228491302563846
    - https://www.virustotal.com/gui/file/c1f27d9795a2eba630db8a043580a0761798f06370fb1317067805f8a845b00c
author: Diego Perez (@darkquassar), Markus Neis, Swisscom (Improve Rule), Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2019-02-22
modified: 2025-05-12
tags:
    - attack.stealth
    - attack.t1140
    - attack.t1218.005
    - attack.execution
    - attack.t1059.007
    - cve.2020-1599
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\mshta.exe'
        - OriginalFileName: 'mshta.exe'
    selection_cli:
        CommandLine|contains:
            - '.7z'
            - '.avi'
            - '.bat'
            - '.bmp'
            - '.conf'
            - '.csv'
            - '.dll'
            - '.doc'
            - '.gif'
            - '.gz'
            - '.ini'
            - '.jpe'
            - '.jpg'
            - '.json'
            - '.lnk'
            - '.log'
            - '.mkv'
            - '.mp3'
            - '.mp4'
            - '.pdf'
            - '.png'
            - '.ppt'
            - '.rar'
            - '.rtf'
            - '.svg'
            - '.tar'
            - '.tmp'
            - '.txt'
            - '.xls'
            - '.xml'
            - '.yaml'
            - '.yml'
            - '.zip'
            - 'vbscript'
            # - '.chm'  # could be prone to false positives
            # - '.exe'
    condition: all of selection_*
falsepositives:
    - False positives depend on scripts and administrative tools used in the monitored environment
level: high

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_img

selection_img:
    - Image|endswith: '\mshta.exe'
    - OriginalFileName: 'mshta.exe'

Stage 2: selection_cli

selection_cli:
    CommandLine|contains:
        - '.7z'
        - '.avi'
        - '.bat'
        - '.bmp'
        - '.conf'
        - '.csv'
        - '.dll'
        - '.doc'
        - '.gif'
        - '.gz'
        - '.ini'
        - '.jpe'
        - '.jpg'
        - '.json'
        - '.lnk'
        - '.log'
        - '.mkv'
        - '.mp3'
        - '.mp4'
        - '.pdf'
        - '.png'
        - '.ppt'
        - '.rar'
        - '.rtf'
        - '.svg'
        - '.tar'
        - '.tmp'
        - '.txt'
        - '.xls'
        - '.xml'
        - '.yaml'
        - '.yml'
        - '.zip'
        - 'vbscript'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • .7z corpus 2 (sigma 2)
  • .avi
  • .bat corpus 10 (sigma 9, elastic 1)
  • .bmp corpus 3 (sigma 2, elastic 1)
  • .conf
  • .csv corpus 2 (sigma 2)
  • .dll corpus 16 (sigma 16)
  • .doc corpus 4 (sigma 4)
  • .gif corpus 9 (sigma 8, elastic 1)
  • .gz
  • .ini
  • .jpe
  • .jpg corpus 8 (sigma 7, elastic 1)
  • .json
  • .lnk corpus 3 (sigma 3)
  • .log corpus 4 (sigma 4)
  • .mkv
  • .mp3 corpus 2 (sigma 2)
  • .mp4
  • .pdf corpus 3 (sigma 3)
  • .png corpus 8 (sigma 7, elastic 1)
  • .ppt corpus 4 (sigma 4)
  • .rar corpus 2 (sigma 2)
  • .rtf corpus 2 (sigma 2)
  • .svg corpus 2 (sigma 2)
  • .tar
  • .tmp corpus 3 (sigma 3)
  • .txt corpus 9 (sigma 9)
  • .xls corpus 4 (sigma 4)
  • .xml corpus 6 (sigma 4, splunk 2)
  • .yaml
  • .yml corpus 2 (sigma 2)
  • .zip corpus 5 (sigma 5)
  • vbscript corpus 3 (sigma 2, splunk 1)
field:"CommandLine" kind:match
Imageends_with
  • \mshta.exe corpus 67 (sigma 66, splunk 1)
field:"Image" kind:ends_with value:"\mshta.exe"
OriginalFileNameeq
  • mshta.exe corpus 40 (elastic 21, sigma 13, splunk 6)
field:"OriginalFileName" kind:eq value:"mshta.exe"

Network Connection Initiated From Users\Public Folder

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

Detects a network connection initiated from a process located in the "C:\Users\Public" folder. Attacker are known to drop their malicious payloads and malware in this directory as its writable by everyone. Use this rule to hunt for potential suspicious or uncommon activity in your environement.

Known False Positives

  • Likely from legitimate third party application that execute from the "Public" directory.

MITRE ATT&CK Coverage

TacticTechniques
Command & Control

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 3: Network connection

Rule Body

title: Network Connection Initiated From Users\Public Folder
id: bcb03938-9f8b-487d-8d86-e480691e1d71
related:
    - id: 7b434893-c57d-4f41-908d-6a17bf1ae98f
      type: derived
status: test
description: |
    Detects a network connection initiated from a process located in the "C:\Users\Public" folder.
    Attacker are known to drop their malicious payloads and malware in this directory as its writable by everyone.
    Use this rule to hunt for potential suspicious or uncommon activity in your environement.
references:
    - https://docs.google.com/spreadsheets/d/17pSTDNpa0sf6pHeRhusvWG6rThciE8CsXTSlDUAZDyo
author: Florian Roth (Nextron Systems)
date: 2024-05-31
tags:
    - attack.command-and-control
    - attack.t1105
    - detection.threat-hunting
logsource:
    category: network_connection
    product: windows
detection:
    selection:
        Initiated: 'true'
        Image|contains: ':\Users\Public\'
    filter_optional_ibm:
        Image|contains: ':\Users\Public\IBM\ClientSolutions\Start_Programs\' # IBM Client Solutions Default Location (Added by Tim Shelton - https://github.com/SigmaHQ/sigma/pull/3053/files)
    condition: selection and not 1 of filter_optional_*
falsepositives:
    - Likely from legitimate third party application that execute from the "Public" directory.
level: medium

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_optional_*

Stage 1: selection

selection:
    Initiated: 'true'
    Image|contains: ':\Users\Public\'

Stage 2: not filter_optional_ibm

filter_optional_ibm:
    Image|contains: ':\Users\Public\IBM\ClientSolutions\Start_Programs\'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imagematch
  • :\Users\Public\ corpus 13 (sigma 13)
field:"Image" kind:match value:":\Users\Public\"
Initiatedeq
  • true corpus 50 (sigma 50)
field:"Initiated" kind:eq value:"true"

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
Imagematch:\Users\Public\IBM\ClientSolutions\Start_Programs\excludes:Image field:"Image" value:":\Users\Public\IBM\ClientSolutions\Start_Programs\"

OpenCanary - SNMP OID Request

#
Status
test
Severity
high
Author
Security Onion Solutions
Source
github.com/SigmaHQ/sigma

Detects instances where an SNMP service on an OpenCanary node has had an OID request.

Known False Positives

  • Unlikely

MITRE ATT&CK Coverage

Rule Body

title: OpenCanary - SNMP OID Request
id: e9856028-fd4e-46e6-b3d1-10f7ceb95078
status: test
description: Detects instances where an SNMP service on an OpenCanary node has had an OID request.
references:
    - https://opencanary.readthedocs.io/en/latest/starting/configuration.html#services-configuration
    - https://github.com/thinkst/opencanary/blob/a0896adfcaf0328cfd5829fe10d2878c7445138e/opencanary/logger.py#L52
author: Security Onion Solutions
date: 2024-03-08
tags:
    - attack.discovery
    - attack.lateral-movement
    - attack.t1016
    - attack.t1021
logsource:
    category: application
    product: opencanary
detection:
    selection:
        logtype: 13001
    condition: selection
falsepositives:
    - Unlikely
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    logtype: 13001

Indicators

These rows show field, operator, and value matches.

Password Policy Discovery - Linux

#
Status
stable
Severity
low
Author
Ömer Günal, oscd.community, Pawel Mazur
Source
github.com/SigmaHQ/sigma

Detects password policy discovery commands

Known False Positives

  • Legitimate administration activities

MITRE ATT&CK Coverage

TacticTechniques
Discovery

Telemetry Coverage

Rule Body

title: Password Policy Discovery - Linux
id: ca94a6db-8106-4737-9ed2-3e3bb826af0a
status: stable
description: Detects password policy discovery commands
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1201/T1201.md
    - https://linux.die.net/man/1/chage
    - https://man7.org/linux/man-pages/man1/passwd.1.html
    - https://superuser.com/questions/150675/how-to-display-password-policy-information-for-a-user-ubuntu
author: Ömer Günal, oscd.community, Pawel Mazur
date: 2020-10-08
modified: 2024-12-01
tags:
    - attack.discovery
    - attack.t1201
logsource:
    product: linux
    service: auditd
detection:
    selection_files:
        type: 'PATH'
        name:
            - '/etc/login.defs'
            - '/etc/pam.d/auth'
            - '/etc/pam.d/common-account'
            - '/etc/pam.d/common-auth'
            - '/etc/pam.d/common-password'
            - '/etc/pam.d/system-auth'
            - '/etc/security/pwquality.conf'
    selection_chage:
        type: 'EXECVE'
        a0: 'chage'
        a1:
            - '--list'
            - '-l'
    selection_passwd:
        type: 'EXECVE'
        a0: 'passwd'
        a1:
            - '-S'
            - '--status'
    condition: 1 of selection_*
falsepositives:
    - Legitimate administration activities
level: low

Stages and Predicates

Stage 0: condition

1 of selection_*

Stage 1: selection_files

selection_files:
    type: 'PATH'
    name:
        - '/etc/login.defs'
        - '/etc/pam.d/auth'
        - '/etc/pam.d/common-account'
        - '/etc/pam.d/common-auth'
        - '/etc/pam.d/common-password'
        - '/etc/pam.d/system-auth'
        - '/etc/security/pwquality.conf'

Stage 2: selection_chage

selection_chage:
    type: 'EXECVE'
    a0: 'chage'
    a1:
        - '--list'
        - '-l'

Stage 3: selection_passwd

selection_passwd:
    type: 'EXECVE'
    a0: 'passwd'
    a1:
        - '-S'
        - '--status'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
a0eq
  • chage
  • passwd
field:"a0" kind:eq
a1eq
  • --list
  • --status
  • -S
  • -l
field:"a1" kind:eq
nameeq
  • /etc/login.defs
  • /etc/pam.d/auth
  • /etc/pam.d/common-account
  • /etc/pam.d/common-auth
  • /etc/pam.d/common-password
  • /etc/pam.d/system-auth corpus 2 (sigma 2)
  • /etc/security/pwquality.conf
field:"name" kind:eq
typeeq
  • EXECVE corpus 37 (sigma 31, splunk 6)
  • PATH corpus 19 (sigma 12, splunk 7)
field:"type" kind:eq

Potential CVE-2022-21587 Exploitation Attempt

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

Detects potential exploitation attempts of CVE-2022-21587 an arbitrary file upload vulnerability impacting Oracle E-Business Suite (EBS). CVE-2022-21587 can lead to unauthenticated remote code execution.

Known False Positives

  • Vulnerability Scanners

MITRE ATT&CK Coverage

TacticTechniques
Initial Access

Rule Body

title: Potential CVE-2022-21587 Exploitation Attempt
id: d033cb8a-8669-4a8e-a974-48d4185a8503
status: test
description: Detects potential exploitation attempts of CVE-2022-21587 an arbitrary file upload vulnerability impacting Oracle E-Business Suite (EBS). CVE-2022-21587 can lead to unauthenticated remote code execution.
references:
    - https://www.rapid7.com/blog/post/2023/02/07/etr-cve-2022-21587-rapid7-observed-exploitation-of-oracle-e-business-suite-vulnerability/
    - https://attackerkb.com/topics/Bkij5kK1qK/cve-2022-21587/rapid7-analysis
    - https://github.com/hieuminhnv/CVE-2022-21587-POC
    - https://blog.viettelcybersecurity.com/cve-2022-21587-oracle-e-business-suite-unauth-rce/
author: Isa Almannaei
date: 2023-02-13
tags:
    - attack.initial-access
    - attack.t1190
    - cve.2022-21587
    - detection.emerging-threats
logsource:
    category: webserver
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains:
            - '/OA_HTML/BneViewerXMLService?bne:uueupload=TRUE'
            - '/OA_HTML/BneUploaderService?bne:uueupload=TRUE'
            - '/OA_HTML/BneDownloadService?bne:uueupload=TRUE'
            - '/OA_HTML/BneOfflineLOVService?bne:uueupload=TRUE'
    condition: selection
falsepositives:
    - Vulnerability Scanners
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    cs-method: 'POST'
    cs-uri-query|contains:
        - '/OA_HTML/BneViewerXMLService?bne:uueupload=TRUE'
        - '/OA_HTML/BneUploaderService?bne:uueupload=TRUE'
        - '/OA_HTML/BneDownloadService?bne:uueupload=TRUE'
        - '/OA_HTML/BneOfflineLOVService?bne:uueupload=TRUE'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
cs-methodeq
  • POST
field:"cs-method" kind:eq value:"POST"
cs-uri-querymatch
  • /OA_HTML/BneDownloadService?bne:uueupload=TRUE
  • /OA_HTML/BneOfflineLOVService?bne:uueupload=TRUE
  • /OA_HTML/BneUploaderService?bne:uueupload=TRUE
  • /OA_HTML/BneViewerXMLService?bne:uueupload=TRUE
field:"cs-uri-query" kind:match

Potential SSH Tunnel Persistence Install Using A Scheduled Task

#
Status
experimental
Severity
high
Author
Rory Duncan
Source
github.com/SigmaHQ/sigma

Detects the creation of new scheduled tasks via commandline, using Schtasks.exe. This rule detects tasks creating that call OpenSSH, which may indicate the creation of reverse SSH tunnel to the attacker's server.

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: Potential SSH Tunnel Persistence Install Using A Scheduled Task
id: 2daa93a0-a5fb-41c5-8cd8-3c11294bfd1f
status: experimental
description: Detects the creation of new scheduled tasks via commandline, using Schtasks.exe. This rule detects tasks creating that call OpenSSH, which may indicate the creation of reverse SSH tunnel to the attacker's server.
references:
    - https://thedfirreport.com/2023/10/30/netsupport-intrusion-results-in-domain-compromise/
    - https://www.kroll.com/en/insights/publications/cyber/cactus-ransomware-prickly-new-variant-evades-detection
author: Rory Duncan
date: 2025-07-14
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.execution
    - attack.t1053.005
    - attack.command-and-control
logsource:
    product: windows
    category: process_creation
detection:
    selection_img:
        - Image|endswith: '\schtasks.exe'
        - OriginalFileName: 'schtasks.exe'
    selection_cli_sshd:
        CommandLine|contains|all:
            - ' /create '
            - 'sshd.exe'
            - '-f'
    selection_cli_ssh:
        CommandLine|contains|all:
            - ' /create '
            - 'ssh.exe'
            - '-i'
    condition: selection_img and 1 of selection_cli_*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection_img and 1 of selection_cli_*

Stage 1: selection_img

selection_img:
    - Image|endswith: '\schtasks.exe'
    - OriginalFileName: 'schtasks.exe'

Stage 2: selection_cli_sshd

selection_cli_sshd:
    CommandLine|contains|all:
        - ' /create '
        - 'sshd.exe'
        - '-f'

Stage 3: selection_cli_ssh

selection_cli_ssh:
    CommandLine|contains|all:
        - ' /create '
        - 'ssh.exe'
        - '-i'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • /create corpus 15 (sigma 15)
  • -f corpus 9 (sigma 7, splunk 2)
  • -i corpus 7 (sigma 7)
  • ssh.exe
  • sshd.exe
field:"CommandLine" kind:match
Imageends_with
  • \schtasks.exe corpus 55 (sigma 55)
field:"Image" kind:ends_with value:"\schtasks.exe"
OriginalFileNameeq
  • schtasks.exe corpus 29 (sigma 18, elastic 7, splunk 4)
field:"OriginalFileName" kind:eq value:"schtasks.exe"

Potential Startup Shortcut Persistence Via PowerShell.EXE

#
Status
test
Severity
high
Author
Christopher Peacock '@securepeacock', SCYTHE
Source
github.com/SigmaHQ/sigma

Detects PowerShell writing startup shortcuts. This procedure was highlighted in Red Canary Intel Insights Oct. 2021, "We frequently observe adversaries using PowerShell to write malicious .lnk files into the startup directory to establish persistence. Accordingly, this detection opportunity is likely to identify persistence mechanisms in multiple threats. In the context of Yellow Cockatoo, this persistence mechanism eventually launches the command-line script that leads to the installation of a malicious DLL"

Known False Positives

  • Depending on your environment accepted applications may leverage this at times. It is recommended to search for anomalies inidicative of malware.

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 11: FileCreate

Rule Body

title: Potential Startup Shortcut Persistence Via PowerShell.EXE
id: 92fa78e7-4d39-45f1-91a3-8b23f3f1088d
status: test
description: |
    Detects PowerShell writing startup shortcuts.
    This procedure was highlighted in Red Canary Intel Insights Oct. 2021, "We frequently observe adversaries using PowerShell to write malicious .lnk files into the startup directory to establish persistence.
    Accordingly, this detection opportunity is likely to identify persistence mechanisms in multiple threats.
    In the context of Yellow Cockatoo, this persistence mechanism eventually launches the command-line script that leads to the installation of a malicious DLL"
references:
    - https://redcanary.com/blog/intelligence-insights-october-2021/
    - https://github.com/redcanaryco/atomic-red-team/blob/36d49de4c8b00bf36054294b4a1fcbab3917d7c5/atomics/T1547.001/T1547.001.md#atomic-test-7---add-executable-shortcut-link-to-user-startup-folder
author: Christopher Peacock '@securepeacock', SCYTHE
date: 2021-10-24
modified: 2023-02-23
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.t1547.001
logsource:
    product: windows
    category: file_event
detection:
    selection:
        Image|endswith:
            - '\powershell.exe'
            - '\pwsh.exe'
        TargetFilename|contains: '\start menu\programs\startup\'
        TargetFilename|endswith: '.lnk'
    condition: selection
falsepositives:
    - Depending on your environment accepted applications may leverage this at times. It is recommended to search for anomalies inidicative of malware.
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith:
        - '\powershell.exe'
        - '\pwsh.exe'
    TargetFilename|contains: '\start menu\programs\startup\'
    TargetFilename|endswith: '.lnk'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \powershell.exe corpus 181 (sigma 180, splunk 1)
  • \pwsh.exe corpus 166 (sigma 166)
field:"Image" kind:ends_with
TargetFilenameends_with
  • .lnk corpus 6 (sigma 6)
field:"TargetFilename" kind:ends_with value:".lnk"
TargetFilenamematch
  • \start menu\programs\startup\ corpus 5 (sigma 5)
field:"TargetFilename" kind:match value:"\start menu\programs\startup\"

Potential Tampering With RDP Related Registry Keys Via Reg.EXE

#
Status
test
Severity
high
Author
pH-T (Nextron Systems), @Kostastsale, TheDFIRReport
Source
github.com/SigmaHQ/sigma

Detects the execution of "reg.exe" for enabling/disabling the RDP service on the host by tampering with the 'CurrentControlSet\Control\Terminal Server' values

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: Potential Tampering With RDP Related Registry Keys Via Reg.EXE
id: 0d5675be-bc88-4172-86d3-1e96a4476536
status: test
description: Detects the execution of "reg.exe" for enabling/disabling the RDP service on the host by tampering with the 'CurrentControlSet\Control\Terminal Server' values
references:
    - https://thedfirreport.com/2022/02/21/qbot-and-zerologon-lead-to-full-domain-compromise/
    - http://etutorials.org/Microsoft+Products/microsoft+windows+server+2003+terminal+services/Chapter+6+Registry/Registry+Keys+for+Terminal+Services/ # Contain description for most of the keys mentioned here (check it out if you want more information
    - http://woshub.com/rds-shadow-how-to-connect-to-a-user-session-in-windows-server-2012-r2/ # Related to the Shadow RPD technique
    - https://admx.help/HKLM/SOFTWARE/Policies/Microsoft/Windows%20NT/Terminal%20Services # Contain description for most of the keys mentioned here (check it out if you want more information)
    - https://bazaar.abuse.ch/sample/6f3aa9362d72e806490a8abce245331030d1ab5ac77e400dd475748236a6cc81/
    - https://blog.sekoia.io/darkgate-internals/
    - https://blog.talosintelligence.com/understanding-the-phobos-affiliate-structure/
    - https://github.com/redcanaryco/atomic-red-team/blob/02c7d02fe1f1feb0fc7944550408ea8224273994/atomics/T1112/T1112.md#atomic-test-63---disable-remote-desktop-anti-alias-setting-through-registry
    - https://github.com/redcanaryco/atomic-red-team/blob/02c7d02fe1f1feb0fc7944550408ea8224273994/atomics/T1112/T1112.md#atomic-test-64---disable-remote-desktop-security-settings-through-registry
    - https://github.com/redcanaryco/atomic-red-team/blob/dd526047b8c399c312fee47d1e6fb531164da54d/atomics/T1112/T1112.yaml#L790
    - https://learn.microsoft.com/en-us/windows-hardware/customize/desktop/unattend/microsoft-windows-terminalservices-rdp-winstationextensions-securitylayer
    - https://threathunterplaybook.com/hunts/windows/190407-RegModEnableRDPConnections/notebook.html
    - https://twitter.com/SagieSec/status/1469001618863624194?t=HRf0eA0W1YYzkTSHb-Ky1A&s=03 # Related to the Shadow RPD technique
    - https://web.archive.org/web/20200929062532/https://blog.menasec.net/2019/02/threat-hunting-rdp-hijacking-via.html # Related to RDP hijacking via the "ServiceDll" key
    - https://www.trendmicro.com/en_us/research/25/i/unmasking-the-gentlemen-ransomware.html
author: pH-T (Nextron Systems), @Kostastsale, TheDFIRReport
date: 2022-02-12
modified: 2025-11-22
tags:
    - attack.persistence
    - attack.lateral-movement
    - attack.defense-impairment
    - attack.t1021.001
    - attack.t1112
logsource:
    product: windows
    category: process_creation
detection:
    selection_main_img:
        - Image|endswith: '\reg.exe'
        - OriginalFileName: 'reg.exe'
    selection_main_cli:
        CommandLine|contains|all:
            - ' add '
            - '\CurrentControlSet\Control\Terminal Server'
            - 'REG_DWORD'
            - ' /f'
    selection_values_1:
        CommandLine|contains|all:
            - 'Licensing Core'
            - 'EnableConcurrentSessions'
    selection_values_2:
        CommandLine|contains:
            - 'AllowTSConnections'
            - 'fDenyTSConnections'
            - 'fEnableWinStation'
            - 'fSingleSessionPerUser'
            - 'IdleWinStationPoolCount'
            - 'MaxInstanceCount'
            - 'SecurityLayer'
            - 'TSAdvertise'
            - 'TSAppCompat'
            - 'TSEnabled'
            - 'TSUserEnabled'
            - 'WinStations\RDP-Tcp'
    filter_main_values_tls:
        CommandLine|contains|all:
            - 'SecurityLayer'
            - '02'  # TLS Enabled
    condition: all of selection_main_* and 1 of selection_values_* and not 1 of filter_main_*
falsepositives:
    - Unknown
level: high
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_reg_rdp_keys_tamper/info.yml

Stages and Predicates

Stage 0: condition

all of selection_main_* and 1 of selection_values_* and not 1 of filter_main_*

Stage 1: selection_main_img

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

Stage 2: selection_main_cli

selection_main_cli:
    CommandLine|contains|all:
        - ' add '
        - '\CurrentControlSet\Control\Terminal Server'
        - 'REG_DWORD'
        - ' /f'

Stage 3: selection_values_1

selection_values_1:
    CommandLine|contains|all:
        - 'Licensing Core'
        - 'EnableConcurrentSessions'

Stage 4: selection_values_2

selection_values_2:
    CommandLine|contains:
        - 'AllowTSConnections'
        - 'fDenyTSConnections'
        - 'fEnableWinStation'
        - 'fSingleSessionPerUser'
        - 'IdleWinStationPoolCount'
        - 'MaxInstanceCount'
        - 'SecurityLayer'
        - 'TSAdvertise'
        - 'TSAppCompat'
        - 'TSEnabled'
        - 'TSUserEnabled'
        - 'WinStations\RDP-Tcp'

Stage 5: not filter_main_values_tls

filter_main_values_tls:
    CommandLine|contains|all:
        - 'SecurityLayer'
        - '02'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • /f corpus 3 (sigma 3)
  • add corpus 14 (sigma 13, splunk 1)
  • AllowTSConnections
  • EnableConcurrentSessions
  • IdleWinStationPoolCount
  • Licensing Core
  • MaxInstanceCount
  • REG_DWORD
  • SecurityLayer
  • TSAdvertise
  • TSAppCompat
  • TSEnabled
  • TSUserEnabled
  • WinStations\RDP-Tcp
  • \CurrentControlSet\Control\Terminal Server
  • fDenyTSConnections
  • fEnableWinStation
  • fSingleSessionPerUser
field:"CommandLine" kind:match
Imageends_with
  • \reg.exe corpus 58 (sigma 58)
field:"Image" kind:ends_with value:"\reg.exe"
OriginalFileNameeq
  • reg.exe corpus 41 (sigma 32, splunk 8, elastic 1)
field:"OriginalFileName" kind:eq value:"reg.exe"

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
CommandLinematch02excludes:CommandLine field:"CommandLine" value:"02"
CommandLinematchSecurityLayerexcludes:CommandLine field:"CommandLine" value:"SecurityLayer"

PUA - Netcat Suspicious Execution

#
Status
test
Severity
high
Author
frack113, Florian Roth (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects execution of Netcat. Adversaries may use a non-application layer protocol for communication between host and C2 server or among infected hosts within a network

Known False Positives

  • Legitimate ncat use

MITRE ATT&CK Coverage

TacticTechniques
Command & Control

Telemetry Coverage

Rule Body

title: PUA - Netcat Suspicious Execution
id: e31033fc-33f0-4020-9a16-faf9b31cbf08
status: test
description: Detects execution of Netcat. Adversaries may use a non-application layer protocol for communication between host and C2 server or among infected hosts within a network
references:
    - https://nmap.org/ncat/
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1095/T1095.md
    - https://www.revshells.com/
author: frack113, Florian Roth (Nextron Systems)
date: 2021-07-21
modified: 2023-02-08
tags:
    - attack.command-and-control
    - attack.t1095
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        # can not use OriginalFileName as is empty
        Image|endswith:
            - '\nc.exe'
            - '\ncat.exe'
            - '\netcat.exe'
    selection_cmdline:
        # Typical command lines
        CommandLine|contains:
            - ' -lvp '
            - ' -lvnp'
            - ' -l -v -p '
            - ' -lv -p '
            - ' -l --proxy-type http '
            # - ' --exec cmd.exe ' # Not specific enough for netcat
            - ' -vnl --exec '
            - ' -vnl -e '
            - ' --lua-exec '
            - ' --sh-exec '
    condition: 1 of selection_*
falsepositives:
    - Legitimate ncat use
level: high

Stages and Predicates

Stage 0: condition

1 of selection_*

Stage 1: selection_img

selection_img:
    Image|endswith:
        - '\nc.exe'
        - '\ncat.exe'
        - '\netcat.exe'

Stage 2: selection_cmdline

selection_cmdline:
    CommandLine|contains:
        - ' -lvp '
        - ' -lvnp'
        - ' -l -v -p '
        - ' -lv -p '
        - ' -l --proxy-type http '
        - ' -vnl --exec '
        - ' -vnl -e '
        - ' --lua-exec '
        - ' --sh-exec '

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • --lua-exec
  • --sh-exec
  • -l --proxy-type http
  • -l -v -p
  • -lv -p
  • -lvnp
  • -lvp
  • -vnl --exec
  • -vnl -e
field:"CommandLine" kind:match
Imageends_with
  • \nc.exe
  • \ncat.exe
  • \netcat.exe
field:"Image" kind:ends_with

PUA - NimScan Execution

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

Detects usage of NimScan, a portscanner utility. In early 2025, adversaries were observed using this utility to scan for open ports on remote hosts in a compromised environment. This rule identifies the execution of NimScan based on the process image name and specific hash values associated with different versions of the tool.

Known False Positives

  • Legitimate administrator activity

MITRE ATT&CK Coverage

TacticTechniques
Discovery

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: PUA - NimScan Execution
id: 4fd6b1c7-19b8-4488-97f6-00f0924991a3
status: test
description: |
    Detects usage of NimScan, a portscanner utility.
    In early 2025, adversaries were observed using this utility to scan for open ports on remote hosts in a compromised environment.
    This rule identifies the execution of NimScan based on the process image name and specific hash values associated with different versions of the tool.
references:
    - https://x.com/cyberfeeddigest/status/1887041526397587859
    - https://github.com/elddy/NimScan
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-02-05
tags:
    - attack.discovery
    - attack.t1046
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        - Image|endswith: '\NimScan.exe' # Other metadata fields such as originalfilename and product were omitted because they were null
        - Hashes|contains:
              - 'IMPHASH=41BB1C7571B3A724EB83A1D2B96DBB8C' # v1.0.8
              - 'IMPHASH=B1B6ADACB172795480179EFD18A29549' # v1.0.6
              - 'IMPHASH=0D1F896DC7642AD8384F9042F30279C2' # v1.0.4 and v1.0.2
    condition: selection
falsepositives:
    - Legitimate administrator activity
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    - Image|endswith: '\NimScan.exe'
    - Hashes|contains:
          - 'IMPHASH=41BB1C7571B3A724EB83A1D2B96DBB8C'
          - 'IMPHASH=B1B6ADACB172795480179EFD18A29549'
          - 'IMPHASH=0D1F896DC7642AD8384F9042F30279C2'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Hashesmatch
  • IMPHASH=0D1F896DC7642AD8384F9042F30279C2
  • IMPHASH=41BB1C7571B3A724EB83A1D2B96DBB8C
  • IMPHASH=B1B6ADACB172795480179EFD18A29549
field:"Hashes" kind:match
Imageends_with
  • \NimScan.exe
field:"Image" kind:ends_with value:"\NimScan.exe"

Service Started/Stopped Via Wmic.EXE

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

Detects usage of wmic to start or stop a service

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: Service Started/Stopped Via Wmic.EXE
id: 0b7163dc-7eee-4960-af17-c0cd517f92da
status: test
description: Detects usage of wmic to start or stop a service
references:
    - https://sushant747.gitbooks.io/total-oscp-guide/content/privilege_escalation_windows.html
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-06-20
modified: 2023-02-14
tags:
    - attack.execution
    - attack.t1047
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - OriginalFileName: 'wmic.exe'
        - Image|endswith: '\WMIC.exe'
    selection_cli:
        CommandLine|contains|all:
            - ' service '
            - ' call '
        CommandLine|contains:
            - 'stopservice'
            - 'startservice'
    condition: all of selection_*
falsepositives:
    - Unknown
level: medium
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_wmic_service_manipulation/info.yml

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_img

selection_img:
    - OriginalFileName: 'wmic.exe'
    - Image|endswith: '\WMIC.exe'

Stage 2: selection_cli

selection_cli:
    CommandLine|contains|all:
        - ' service '
        - ' call '
    CommandLine|contains:
        - 'stopservice'
        - 'startservice'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • call corpus 2 (sigma 1, splunk 1)
  • service corpus 2 (sigma 2)
  • startservice
  • stopservice
field:"CommandLine" kind:match
Imageends_with
  • \WMIC.exe corpus 62 (sigma 62)
field:"Image" kind:ends_with value:"\WMIC.exe"
OriginalFileNameeq
  • wmic.exe corpus 74 (sigma 38, elastic 18, splunk 18)
field:"OriginalFileName" kind:eq value:"wmic.exe"

Solarwinds SUPERNOVA Webshell Access

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

Detects access to SUPERNOVA webshell as described in Guidepoint report

MITRE ATT&CK Coverage

Rule Body

title: Solarwinds SUPERNOVA Webshell Access
id: a2cee20b-eacc-459f-861d-c02e5d12f1db
status: test
description: Detects access to SUPERNOVA webshell as described in Guidepoint report
references:
    - https://www.guidepointsecurity.com/supernova-solarwinds-net-webshell-analysis/
    - https://www.anquanke.com/post/id/226029
author: Florian Roth (Nextron Systems)
date: 2020-12-17
modified: 2023-01-02
tags:
    - attack.persistence
    - attack.t1505.003
    - detection.emerging-threats
logsource:
    category: webserver
detection:
    selection1:
        cs-uri-query|contains|all:
            - 'logoimagehandler.ashx'
            - 'clazz'
    selection2:
        cs-uri-query|contains: 'logoimagehandler.ashx'
        sc-status: 500
    condition: selection1 or selection2
falsepositives:
    - Unknown
level: critical

Stages and Predicates

Stage 0: condition

selection1 or selection2

Stage 1: selection1

selection1:
    cs-uri-query|contains|all:
        - 'logoimagehandler.ashx'
        - 'clazz'

Stage 2: selection2

selection2:
    cs-uri-query|contains: 'logoimagehandler.ashx'
    sc-status: 500

Indicators

These rows show field, operator, and value matches.

Suspicious Execution of Shutdown to Log Out

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

Detects the rare use of the command line tool shutdown to logoff a user

MITRE ATT&CK Coverage

TacticTechniques
Impact

Telemetry Coverage

Rule Body

title: Suspicious Execution of Shutdown to Log Out
id: ec290c06-9b6b-4338-8b6b-095c0f284f10
status: test
description: Detects the rare use of the command line tool shutdown to logoff a user
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/9e5b12c4912c07562aec7500447b11fa3e17e254/atomics/T1529/T1529.md
    - https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/shutdown
author: frack113
date: 2022-10-01
tags:
    - attack.impact
    - attack.t1529
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith: '\shutdown.exe'
        CommandLine|contains: '/l'
    condition: selection
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith: '\shutdown.exe'
    CommandLine|contains: '/l'

Indicators

These rows show field, operator, and value matches.

Suspicious modification of a user account SPN to enable Kerberoast attack

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

Detects scenarios where an attacker update the Service Principal Name (SPN) of a user account in order to enable Kerberoast attack and crack its password.

Known False Positives

  • Rare administrator modifications on user objects

MITRE ATT&CK Coverage

TacticTechniques
Persistence

Telemetry Coverage

Rule Body

title: Suspicious modification of a user account SPN to enable Kerberoast attack
description: Detects scenarios where an attacker update the Service Principal Name (SPN) of a user account in order to enable Kerberoast attack and crack its password.
requirements: auditing SACL ("Write all properties") must be placed on the OU to monitor using the Active Directory console (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/TA0003-Persistence/T1098.xxx-Account%20manipulation
- https://docs.microsoft.com/en-us/windows/security/threat-protection/auditing/event-5136
- https://github.com/S1ckB0y1337/Active-Directory-Exploitation-Cheat-Sheet#force-set-spn
- https://docs.microsoft.com/en-us/troubleshoot/windows-server/windows-security/use-audit-active-directory-objects-track-events
tags:
- attack.persistence
- attack.t1098
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  service: security
detection:
  selection:
    EventID: 5136 # ID 4738 doesn't report any changes about SPN changes
    AttributeLDAPDisplayName: servicePrincipalName
    ObjectClass: user
    OperationType: '%%14674' # Value is added
  filter:
    AttributeValue: '-'
  condition: selection and not filter
falsepositives:
- Rare administrator modifications on user objects
level: high

Stages and Predicates

Stage 0: condition

selection and not filter

Stage 1: selection

selection:
  EventID: 5136
  AttributeLDAPDisplayName: servicePrincipalName
  ObjectClass: user
  OperationType: '%%14674'

Stage 2: not filter

filter:
  AttributeValue: '-'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
AttributeLDAPDisplayNameeq
  • servicePrincipalName corpus 8 (sigma 4, splunk 3, elastic 1)
field:"AttributeLDAPDisplayName" kind:eq value:"servicePrincipalName"
ObjectClasseq
  • user corpus 5 (sigma 2, splunk 2, elastic 1)
field:"ObjectClass" kind:eq value:"user"
OperationTypeeq
  • %%14674 corpus 16 (sigma 9, splunk 4, elastic 3)
field:"OperationType" kind:eq value:"%%14674"

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
AttributeValueeq-excludes:AttributeValue field:"AttributeValue" value:"-"

System Integrity Protection (SIP) Enumeration

#
Status
test
Severity
low
Author
Joseliyo Sanchez, @Joseliyo_Jstnk
Source
github.com/SigmaHQ/sigma

Detects the use of csrutil to view the Configure System Integrity Protection (SIP) status. This technique is used in post-exploit scenarios.

Known False Positives

  • Legitimate administration activities

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: System Integrity Protection (SIP) Enumeration
id: 53821412-17b0-4147-ade0-14faae67d54b
status: test
description: |
    Detects the use of csrutil to view the Configure System Integrity Protection (SIP) status. This technique is used in post-exploit scenarios.
references:
    - https://ss64.com/osx/csrutil.html
    - https://objective-see.org/blog/blog_0x6D.html
    - https://www.welivesecurity.com/2017/10/20/osx-proton-supply-chain-attack-elmedia/
    - https://www.virustotal.com/gui/file/05a2adb266ec6c0ba9ed176d87d8530e71e845348c13caf9f60049760c312cd3/behavior
author: Joseliyo Sanchez, @Joseliyo_Jstnk
date: 2024-01-02
tags:
    - attack.discovery
    - attack.t1518.001
logsource:
    product: macos
    category: process_creation
detection:
    # VT Query: behavior_processes:"csrutil status" p:5+ type:mac
    selection:
        Image|endswith: '/csrutil'
        CommandLine|contains: 'status'
    condition: selection
falsepositives:
    - Legitimate administration activities
level: low

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith: '/csrutil'
    CommandLine|contains: 'status'

Indicators

These rows show field, operator, and value matches.

TropicTrooper Campaign November 2018

#
Status
stable
Severity
high
Author
@41thexplorer, Microsoft Defender ATP
Source
github.com/SigmaHQ/sigma

Detects TropicTrooper activity, an actor who targeted high-profile organizations in the energy and food and beverage sectors in Asia

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: TropicTrooper Campaign November 2018
id: 8c7090c3-e0a0-4944-bd08-08c3a0cecf79
status: stable
description: Detects TropicTrooper activity, an actor who targeted high-profile organizations in the energy and food and beverage sectors in Asia
references:
    - https://www.microsoft.com/en-us/security/blog/2018/11/28/windows-defender-atp-device-risk-score-exposes-new-cyberattack-drives-conditional-access-to-protect-networks/
author: '@41thexplorer, Microsoft Defender ATP'
date: 2019-11-12
modified: 2020-08-27
tags:
    - attack.execution
    - attack.t1059.001
    - detection.emerging-threats
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        CommandLine|contains: 'abCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCc'
    condition: selection
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    CommandLine|contains: 'abCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCc'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • abCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCc
field:"CommandLine" kind:match value:"abCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCc"

Unsigned Binary Loaded From Suspicious Location

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

Detects Code Integrity (CI) engine blocking processes from loading unsigned DLLs residing in suspicious locations

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Unsigned Binary Loaded From Suspicious Location
id: 8289bf8c-4aca-4f5a-9db3-dc3d7afe5c10
status: test
description: Detects Code Integrity (CI) engine blocking processes from loading unsigned DLLs residing in suspicious locations
references:
    - https://github.com/nasbench/EVTX-ETW-Resources/blob/45fd5be71a51aa518b1b36d4e1f36af498084e27/ETWEventsList/CSV/Windows11/21H2/W11_21H2_Pro_20220719_22000.795/Providers/Microsoft-Windows-Security-Mitigations.csv
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-08-03
modified: 2022-09-28
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.execution
    - attack.stealth
    - attack.t1574.001
logsource:
    product: windows
    service: security-mitigations
detection:
    selection:
        EventID:
            - 11
            - 12
        ImageName|contains:
            - '\Users\Public\'
            - '\PerfLogs\'
            - '\Desktop\'
            - '\Downloads\'
            - '\AppData\Local\Temp\'
            - 'C:\Windows\TEMP\'
    condition: selection
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    EventID:
        - 11
        - 12
    ImageName|contains:
        - '\Users\Public\'
        - '\PerfLogs\'
        - '\Desktop\'
        - '\Downloads\'
        - '\AppData\Local\Temp\'
        - 'C:\Windows\TEMP\'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
ImageNamematch
  • C:\Windows\TEMP\ corpus 2 (sigma 2)
  • \AppData\Local\Temp\ corpus 11 (sigma 10, splunk 1)
  • \Desktop\ corpus 6 (sigma 6)
  • \Downloads\ corpus 9 (sigma 9)
  • \PerfLogs\ corpus 4 (sigma 4)
  • \Users\Public\ corpus 9 (sigma 9)
field:"Image" kind:match

Windows Firewall Settings Have Been Changed

#
Status
test
Severity
low
Author
frack113, Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects activity when the settings of the Windows firewall have been changed

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Windows Firewall Settings Have Been Changed
id: 00bb5bd5-1379-4fcf-a965-a5b6f7478064
status: test
description: Detects activity when the settings of the Windows firewall have been changed
references:
    - https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-r2-and-2008/dd364427(v=ws.10)
author: frack113, Nasreddine Bencherchali (Nextron Systems)
date: 2022-02-19
modified: 2023-04-21
tags:
    - attack.defense-impairment
    - attack.t1686.003
logsource:
    product: windows
    service: firewall-as
detection:
    selection:
        EventID:
            - 2002 # A Windows Defender Firewall setting has changed.
            - 2083 # A Windows Defender Firewall setting has changed. (Windows 11)
            - 2003 # A Windows Firewall setting in the profile has changed
            - 2082 # A Windows Defender Firewall setting in the %1 profile has changed. (Windows 11)
            - 2008  # Windows Firewall Group Policy settings have changed. The new settings have been applied
            # - 2010  # Network profile changed on an interface.
    condition: selection
level: low

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    EventID:
        - 2002
        - 2083
        - 2003
        - 2082
        - 2008

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