Sigma rules: 1y

title: Attempts of Kerberos Coercion Via DNS SPN Spoofing
id: 0ed99dda-6a35-11ef-8c99-0242ac120002
related:
    - id: b07e58cf-cacc-4135-8473-ccb2eba63dd2
      type: similar
status: experimental
description: |
    Detects the presence of "UWhRC....AAYBAAAA" pattern in command line.
    The pattern "1UWhRCAAAAA..BAAAA" is a base64-encoded signature that corresponds to a marshaled CREDENTIAL_TARGET_INFORMATION structure.
    Attackers can use this technique to coerce authentication from victim systems to attacker-controlled hosts.
    It is one of the strong indicators of a Kerberos coercion attack, where adversaries manipulate DNS records
    to spoof Service Principal Names (SPNs) and redirect authentication requests like in CVE-2025-33073.
    If you see this pattern in the command line, it is likely an attempt to add spoofed Service Principal Names (SPNs) to DNS records,
    or checking for the presence of such records through the `nslookup` command.
references:
    - https://www.synacktiv.com/publications/ntlm-reflection-is-dead-long-live-ntlm-reflection-an-in-depth-analysis-of-cve-2025
    - https://googleprojectzero.blogspot.com/2021/10/using-kerberos-for-authentication-relay.html
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-06-20
tags:
    - attack.collection
    - attack.credential-access
    - attack.persistence
    - attack.privilege-escalation
    - attack.t1557.001
    - attack.t1187
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        CommandLine|contains|all:
            - 'UWhRCA'
            - 'BAAAA'
    condition: selection
falsepositives:
    - Unknown
level: high

title: Atypical Travel
id: 1a41023f-1e70-4026-921a-4d9341a9038e
status: test
description: Identifies two sign-ins originating from geographically distant locations, where at least one of the locations may also be atypical for the user, given past behavior.
references:
    - https://learn.microsoft.com/en-us/entra/id-protection/concept-identity-protection-risks#atypical-travel
    - https://learn.microsoft.com/en-us/entra/architecture/security-operations-user-accounts#unusual-sign-ins
author: Mark Morowczynski '@markmorow', Gloria Lee, '@gleeiamglo'
date: 2023-09-03
tags:
    - attack.stealth
    - attack.t1078
    - attack.persistence
    - attack.privilege-escalation
    - attack.initial-access
logsource:
    product: azure
    service: riskdetection
detection:
    selection:
        riskEventType: 'unlikelyTravel'
    condition: selection
falsepositives:
    - We recommend investigating the sessions flagged by this detection in the context of other sign-ins from the user.
level: high

title: AWS RDS Master Password Change
id: 8a63cdd4-6207-414a-85bc-7e032bd3c1a2
status: test
description: Detects the change of database master password. It may be a part of data exfiltration.
references:
    - https://github.com/RhinoSecurityLabs/pacu/blob/866376cd711666c775bbfcde0524c817f2c5b181/pacu/modules/rds__explore_snapshots/main.py
author: faloker
date: 2020-02-12
modified: 2022-10-05
tags:
    - attack.exfiltration
    - attack.t1020
logsource:
    product: aws
    service: cloudtrail
detection:
    selection_source:
        eventSource: rds.amazonaws.com
        responseElements.pendingModifiedValues.masterUserPassword|contains: '*'
        eventName: ModifyDBInstance
    condition: selection_source
falsepositives:
    - Benign changes to a db instance
level: medium

title: AWS SecurityHub Findings Evasion
id: a607e1fe-74bf-4440-a3ec-b059b9103157
status: stable
description: Detects the modification of the findings on SecurityHub.
references:
    - https://docs.aws.amazon.com/cli/latest/reference/securityhub/
author: Sittikorn S
date: 2021-06-28
tags:
    - attack.defense-impairment
    - attack.t1685
logsource:
    product: aws
    service: cloudtrail
detection:
    selection:
        eventSource: securityhub.amazonaws.com
        eventName:
            - 'BatchUpdateFindings'
            - 'DeleteInsight'
            - 'UpdateFindings'
            - 'UpdateInsight'
    condition: selection
falsepositives:
    - System or Network administrator behaviors
    - DEV, UAT, SAT environment. You should apply this rule with PROD environment only.
level: high

title: Clipboard Data Collection Via Pbpaste
id: d8af0da1-2959-40f9-a3e4-37a6aa1228b7
status: test
description: |
    Detects execution of the "pbpaste" utility, which retrieves the contents of the clipboard (a.k.a. pasteboard) and writes them to the standard output (stdout).
    The utility is often used for creating new files with the clipboard content or for piping clipboard contents to other commands.
    It can also be used in shell scripts that may require clipboard content as input.
    Attackers can abuse this utility in order to collect data from the user clipboard, which may contain passwords or sensitive information.
    Use this rule to hunt for potential abuse of the utility by looking at the parent process and any potentially suspicious command line content.
references:
    - https://www.loobins.io/binaries/pbpaste/
    - https://medium.com/@NullByteWht/hacking-macos-how-to-dump-1password-keepassx-lastpass-passwords-in-plaintext-723c5b1c311b
    - https://media.defense.gov/2021/Jul/19/2002805003/-1/-1/1/CSA_CHINESE_STATE-SPONSORED_CYBER_TTPS.PDF
author: Daniel Cortez
date: 2024-07-30
tags:
    - attack.collection
    - attack.credential-access
    - attack.t1115
    - detection.threat-hunting
logsource:
    product: macos
    category: process_creation
detection:
    selection:
        Image|endswith: '/pbpaste'
    condition: selection
falsepositives:
    - Legitimate administration activities
level: medium

title: Copy .DMP/.DUMP Files From Remote Share Via Cmd.EXE
id: 044ba588-dff4-4918-9808-3f95e8160606
status: test
description: Detects usage of the copy builtin cmd command to copy files with the ".dmp"/".dump" extension from a remote share
references:
    - https://thedfirreport.com/2022/09/26/bumblebee-round-two/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-09-27
modified: 2023-09-12
tags:
    - attack.credential-access
logsource:
    category: process_creation
    product: windows
detection:
    # Example: copy \\<host>\\<folder>\\process.dmp C:\Users\process.dmp
    selection_img:
        - Image|endswith: '\cmd.exe'
        - OriginalFileName: 'Cmd.Exe'
    selection_cli:
        CommandLine|contains|all:
            - 'copy '
            - ' \\\\'
        CommandLine|contains:
            - '.dmp'
            - '.dump'
            - '.hdmp'
    condition: all of selection_*
falsepositives:
    - Unknown
level: high

title: Credentials In Files - Linux
id: df3fcaea-2715-4214-99c5-0056ea59eb35
status: test
description: 'Detecting attempts to extract passwords with grep'
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1552.001/T1552.001.md
author: 'Igor Fits, oscd.community'
date: 2020-10-15
modified: 2023-04-30
tags:
    - attack.credential-access
    - attack.t1552.001
logsource:
    product: linux
    service: auditd
detection:
    selection:
        type: 'EXECVE'
    keywords:
        '|all':
            - 'grep'
            - 'password'
    condition: selection and keywords
falsepositives:
    - Unknown
level: high

title: Exchange PowerShell Cmdlet History Deleted
id: a55349d8-9588-4c5a-8e3b-1925fe2a4ffe
status: test
description: Detects the deletion of the Exchange PowerShell cmdlet History logs which may indicate an attempt to destroy forensic evidence
references:
    - https://m365internals.com/2022/10/07/hunting-in-on-premises-exchange-server-logs/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-10-26
modified: 2022-12-30
tags:
    - attack.stealth
    - attack.t1070
logsource:
    category: file_delete
    product: windows
detection:
    selection:
        TargetFilename|startswith: '\Logging\CmdletInfra\LocalPowerShell\Cmdlet\'
        TargetFilename|contains: '_Cmdlet_'
    condition: selection
falsepositives:
    - Possible FP during log rotation
level: high

title: Flash Player Update from Suspicious Location
id: 4922a5dd-6743-4fc2-8e81-144374280997
status: test
description: Detects a flashplayer update from an unofficial location
references:
    - https://gist.github.com/roycewilliams/a723aaf8a6ac3ba4f817847610935cfb
author: Florian Roth (Nextron Systems)
date: 2017-10-25
modified: 2022-08-08
tags:
    - attack.initial-access
    - attack.stealth
    - attack.t1189
    - attack.execution
    - attack.t1204.002
    - attack.t1036.005
logsource:
    category: proxy
detection:
    selection:
        - c-uri|contains: '/flash_install.php'
        - c-uri|endswith: '/install_flash_player.exe'
    filter:
        cs-host|endswith: '.adobe.com'
    condition: selection and not filter
falsepositives:
    - Unknown flash download locations
level: high

title: Forfiles.EXE Child Process Masquerading
id: f53714ec-5077-420e-ad20-907ff9bb2958
status: test
description: |
    Detects the execution of "forfiles" from a non-default location, in order to potentially spawn a custom "cmd.exe" from the current working directory.
references:
    - https://www.hexacorn.com/blog/2023/12/31/1-little-known-secret-of-forfiles-exe/
author: Nasreddine Bencherchali (Nextron Systems), Anish Bogati
date: 2024-01-05
tags:
    - attack.stealth
    - attack.t1036
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        # Notes:
        #   - The parent must not have CLI options
        #   - The Child Image must be named "cmd" as its hardcoded in the "forfiles" binary
        #   - The Child CLI will always contains "/c echo" as its hardcoded in the original "forfiles" binary
        ParentCommandLine|endswith:
            - '.exe'
            - '.exe"'
        Image|endswith: '\cmd.exe'
        CommandLine|startswith: '/c echo "'
    filter_main_parent_not_sys:
        ParentImage|contains:
            - ':\Windows\System32\'
            - ':\Windows\SysWOW64\'
        ParentImage|endswith: '\forfiles.exe'
        Image|contains:
            - ':\Windows\System32\'
            - ':\Windows\SysWOW64\'
        Image|endswith: '\cmd.exe'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: high

title: Gzip Archive Decode Via PowerShell
id: 98767d61-b2e8-4d71-b661-e36783ee24c1
status: test
description: Detects attempts of decoding encoded Gzip archives via PowerShell.
references:
    - https://www.zscaler.com/blogs/security-research/onenote-growing-threat-malware-distribution
author: Hieu Tran
date: 2023-03-13
tags:
    - attack.command-and-control
    - attack.t1132.001
logsource:
    product: windows
    category: process_creation
detection:
    selection:
        CommandLine|contains|all:
            - 'GZipStream'
            - '::Decompress'
    condition: selection
falsepositives:
    - Legitimate administrative scripts may use this functionality. Use "ParentImage" in combination with the script names and allowed users and applications to filter legitimate executions
level: medium

title: HackTool - RedMimicry Winnti Playbook Execution
id: 95022b85-ff2a-49fa-939a-d7b8f56eeb9b
status: test
description: Detects actions caused by the RedMimicry Winnti playbook a automated breach emulations utility
references:
    - https://redmimicry.com/posts/redmimicry-winnti/
author: Alexander Rausch
date: 2020-06-24
modified: 2023-03-01
tags:
    - attack.execution
    - attack.stealth
    - attack.t1106
    - attack.t1059.003
    - attack.t1218.011
logsource:
    product: windows
    category: process_creation
detection:
    selection:
        Image|endswith:
            - '\rundll32.exe'
            - '\cmd.exe'
        CommandLine|contains:
            - 'gthread-3.6.dll'
            - '\Windows\Temp\tmp.bat'
            - 'sigcmm-2.4.dll'
    condition: selection
falsepositives:
    - Unknown
level: high

title: IE ZoneMap Setting Downgraded To MyComputer Zone For HTTP Protocols
id: 3fd4c8d7-8362-4557-a8e6-83b29cc0d724
related:
    - id: 10344bb3-7f65-46c2-b915-2d00d47be5b0
      type: similar
status: test
description: |
    Detects changes to Internet Explorer's (IE / Windows Internet properties) ZoneMap configuration of the "HTTP" and "HTTPS" protocols to point to the "My Computer" zone. This allows downloaded files from the Internet to be granted the same level of trust as files stored locally.
references:
    - https://twitter.com/M_haggis/status/1699056847154725107
    - https://twitter.com/JAMESWT_MHT/status/1699042827261391247
    - https://learn.microsoft.com/en-us/troubleshoot/developer/browsers/security-privacy/ie-security-zones-registry-entries
    - https://www.virustotal.com/gui/file/339ff720c74dc44265b917b6d3e3ba0411d61f3cd3c328e9a2bae81592c8a6e5/content
author: Nasreddine Bencherchali (Nextron Systems), Michael Haag (idea)
date: 2023-09-05
tags:
    - attack.stealth
logsource:
    product: windows
    category: registry_set
detection:
    selection:
        TargetObject|contains: '\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap\ProtocolDefaults'
        TargetObject|endswith:
            - '\http'
            - '\https'
        Details|contains: 'DWORD (0x00000000)'
    condition: selection
falsepositives:
    - Unknown
level: high

title: Important Windows Service Terminated Unexpectedly
id: 56abae0c-6212-4b97-adc0-0b559bb950c3
status: test
description: Detects important or interesting Windows services that got terminated unexpectedly.
references:
    - https://www.randori.com/blog/vulnerability-analysis-queuejumper-cve-2023-21554/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-04-14
tags:
    - attack.stealth
logsource:
    product: windows
    service: system
detection:
    selection_eid:
        Provider_Name: 'Service Control Manager'
        EventID: 7034 # The X service terminated unexpectedly. It has done this Y time(s).
    selection_name:
        # Note that these names contained in "param1" are "Display Names" and are language specific. If you're using a non-english system these can and will be different
        - param1|contains: 'Message Queuing'
        # Use this If you collect the binary value provided from this event, which is the wide hex encoded value of the service name.
        - Binary|contains:
              - '4d0053004d005100' # MSMQ (Microsoft Message Queuing). Encoded in upper case just in case
              - '6d0073006d007100' # msmq
    condition: all of selection_*
falsepositives:
    - Rare false positives could occur since service termination could happen due to multiple reasons
level: high

title: Linux Base64 Encoded Shebang In CLI
id: fe2f9663-41cb-47e2-b954-8a228f3b9dff
status: test
description: Detects the presence of a base64 version of the shebang in the commandline, which could indicate a malicious payload about to be decoded
references:
    - https://www.trendmicro.com/pl_pl/research/20/i/the-evolution-of-malicious-shell-scripts.html
    - https://github.com/carlospolop/PEASS-ng/tree/master/linPEAS
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-09-15
tags:
    - attack.stealth
    - attack.t1140
logsource:
    product: linux
    category: process_creation
detection:
    selection:
        CommandLine|contains:
            - "IyEvYmluL2Jhc2" # Note: #!/bin/bash"
            - "IyEvYmluL2Rhc2" # Note: #!/bin/dash"
            - "IyEvYmluL3pza" # Note: #!/bin/zsh"
            - "IyEvYmluL2Zpc2" # Note: #!/bin/fish
            - "IyEvYmluL3No" # Note: # !/bin/sh"
    condition: selection
falsepositives:
    - Legitimate administration activities
level: medium

title: MITRE BZAR Indicators for Execution
id: b640c0b8-87f8-4daa-aef8-95a24261dd1d
status: test
description: 'Windows DCE-RPC functions which indicate an execution techniques on the remote system. All credit for the Zeek mapping of the suspicious endpoint/operation field goes to MITRE'
references:
    - https://github.com/mitre-attack/bzar#indicators-for-attck-execution
author: '@neu5ron, SOC Prime'
date: 2020-03-19
modified: 2021-11-27
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.execution
    - attack.t1047
    - attack.t1053.002
    - attack.t1569.002
logsource:
    product: zeek
    service: dce_rpc
detection:
    op1:
        endpoint: 'JobAdd'
        operation: 'atsvc'
    op2:
        endpoint: 'ITaskSchedulerService'
        operation: 'SchRpcEnableTask'
    op3:
        endpoint: 'ITaskSchedulerService'
        operation: 'SchRpcRegisterTask'
    op4:
        endpoint: 'ITaskSchedulerService'
        operation: 'SchRpcRun'
    op5:
        endpoint: 'IWbemServices'
        operation: 'ExecMethod'
    op6:
        endpoint: 'IWbemServices'
        operation: 'ExecMethodAsync'
    op7:
        endpoint: 'svcctl'
        operation: 'CreateServiceA'
    op8:
        endpoint: 'svcctl'
        operation: 'CreateServiceW'
    op9:
        endpoint: 'svcctl'
        operation: 'StartServiceA'
    op10:
        endpoint: 'svcctl'
        operation: 'StartServiceW'
    condition: 1 of op*
falsepositives:
    - Windows administrator tasks or troubleshooting
    - Windows management scripts or software
level: medium

title: NET NGenAssemblyUsageLog Registry Key Tamper
id: 28036918-04d3-423d-91c0-55ecf99fb892
status: test
description: |
  Detects changes to the NGenAssemblyUsageLog registry key.
  .NET Usage Log output location can be controlled by setting the NGenAssemblyUsageLog CLR configuration knob in the Registry or by configuring an environment variable (as described in the next section).
  By simplify specifying an arbitrary value (e.g. fake output location or junk data) for the expected value, a Usage Log file for the .NET execution context will not be created.
references:
    - https://bohops.com/2021/03/16/investigating-net-clr-usage-log-tampering-techniques-for-edr-evasion/
author: frack113
date: 2022-11-18
modified: 2023-08-17
tags:
    - attack.persistence
    - attack.defense-impairment
    - attack.t1112
logsource:
    product: windows
    category: registry_set
detection:
    selection:
        TargetObject|endswith: 'SOFTWARE\Microsoft\.NETFramework\NGenAssemblyUsageLog'
    condition: selection
falsepositives:
    - Unknown
level: high

title: Potential Base64 Encoded User-Agent
id: 894a8613-cf12-48b3-8e57-9085f54aa0c3
related:
    - id: d443095b-a221-4957-a2c4-cd1756c9b747
      type: derived
status: test
description: Detects User Agent strings that end with an equal sign, which can be a sign of base64 encoding.
references:
    - https://blogs.jpcert.or.jp/en/2022/07/yamabot.html
    - https://deviceatlas.com/blog/list-of-user-agent-strings#desktop
author: Florian Roth (Nextron Systems), Brian Ingram (update)
date: 2022-07-08
modified: 2023-05-04
tags:
    - attack.command-and-control
    - attack.t1071.001
logsource:
    category: proxy
detection:
    selection:
        c-useragent|endswith: '='
    condition: selection
falsepositives:
    - Unknown
level: medium

title: Potential CVE-2021-27905 Exploitation Attempt
id: 0bbcd74b-0596-41a4-94a0-4e88a76ffdb3
status: test
description: Detects exploitation attempt of the CVE-2021-27905 which affects all Apache Solr versions prior to and including 8.8.1.
references:
    - https://twitter.com/Al1ex4/status/1382981479727128580
    - https://twitter.com/sec715/status/1373472323538362371
    - https://nsfocusglobal.com/apache-solr-arbitrary-file-read-and-ssrf-vulnerability-threat-alert/
    - https://mp.weixin.qq.com/s?__biz=Mzg3NDU2MTg0Ng==&mid=2247484117&idx=1&sn=2fdab8cbe4b873f8dd8abb35d935d186
    - https://github.com/murataydemir/CVE-2021-27905
author: '@gott_cyber'
date: 2022-12-11
modified: 2023-03-24
tags:
    - attack.initial-access
    - attack.t1190
    - cve.2021-27905
    - detection.emerging-threats
logsource:
    category: webserver
detection:
    selection_request1:
        cs-uri-query|contains|all:
            - '/solr/'
            - '/debug/dump?'
            - 'param=ContentStream'
        sc-status: 200
    selection_request2:
        cs-method: 'GET'
        cs-uri-query|contains|all:
            - '/solr/'
            - 'command=fetchindex'
            - 'masterUrl='
        sc-status: 200
    condition: 1 of selection_*
falsepositives:
    - Vulnerability Scanners
level: medium

title: Potential Snatch Ransomware Activity
id: 5325945e-f1f0-406e-97b8-65104d393fff
status: stable
description: Detects specific process characteristics of Snatch ransomware word document droppers
references:
    - https://news.sophos.com/en-us/2019/12/09/snatch-ransomware-reboots-pcs-into-safe-mode-to-bypass-protection/
author: Florian Roth (Nextron Systems)
date: 2020-08-26
modified: 2025-10-19
tags:
    - attack.execution
    - attack.t1204
    - detection.emerging-threats
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        - CommandLine|re: 'shutdown\s+/r /f /t 00' # Shutdown in safe mode immediately
        - CommandLine|re: 'net\s+stop SuperBackupMan'
    condition: selection
falsepositives:
    - Scripts that shutdown the system immediately and reboot them in safe mode are unlikely
level: high

title: Potential SocGholish Second Stage C2 DNS Query
id: 70761fe8-6aa2-4f80-98c1-a57049c08e66
status: test
description: Detects a DNS query initiated from a "wscript" process for domains matching a specific pattern that was seen being used by SocGholish for its Command and Control traffic
references:
    - https://www.virustotal.com/gui/file/0e2854753d17b1bb534de8e765d5813c9fb584a745978b3d92bc6ca78e3e7735/relations
    - https://www.virustotal.com/gui/file/d5661009c461a8b20e1ad22f48609cc84dd90aee9182e026659dde4d46aaf25e/relations
    - https://www.proofpoint.com/us/blog/threat-insight/part-1-socgholish-very-real-threat-very-fake-update
author: Dusty Miller
date: 2023-02-23
tags:
    - attack.command-and-control
    - attack.t1219.002
    - detection.emerging-threats
logsource:
    product: windows
    category: dns_query
detection:
    selection:
        Image|endswith: '\wscript.exe'
        QueryName|re: '[a-f0-9]{4,8}\.(?:[a-z0-9\-]+\.){2}[a-z0-9\-]+'
    condition: selection
falsepositives:
    - Legitimate domain names matching the regex pattern by chance (e.g. domain controllers dc01.company.co.uk)
level: high

title: Potentially Suspicious Execution Of Regasm/Regsvcs From Uncommon Location
id: cc368ed0-2411-45dc-a222-510ace303cb2
related:
    - id: e9f8f8cc-07cc-4e81-b724-f387db9175e4
      type: derived
status: test
description: Detects potentially suspicious execution of the Regasm/Regsvcs utilities from a potentially suspicious location
references:
    - https://www.fortiguard.com/threat-signal-report/4718?s=09
    - https://lolbas-project.github.io/lolbas/Binaries/Regasm/
    - https://lolbas-project.github.io/lolbas/Binaries/Regsvcs/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-08-25
modified: 2023-02-13
tags:
    - attack.stealth
    - attack.t1218.009
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith:
              - '\Regsvcs.exe'
              - '\Regasm.exe'
        - OriginalFileName:
              - 'RegSvcs.exe'
              - 'RegAsm.exe'
    selection_dir:
        CommandLine|contains:
            # Note: Add more potentially suspicious directories
            - '\AppData\Local\Temp\'
            - '\Microsoft\Windows\Start Menu\Programs\Startup\'
            - '\PerfLogs\'
            - '\Users\Public\'
            - '\Windows\Temp\'
            # - '\Desktop\'
            # - '\Downloads\'
    condition: all of selection_*
falsepositives:
    - Unknown
level: medium

title: PowerShell Set-Acl On Windows Folder
id: 0944e002-e3f6-4eb5-bf69-3a3067b53d73 # ProcCreation Susp
related:
    - id: cae80281-ef23-44c5-873b-fd48d2666f49 # PsScript Low
      type: derived
    - id: bdeb2cff-af74-4094-8426-724dc937f20a # ProcCreation Low
      type: derived
    - id: 3bf1d859-3a7e-44cb-8809-a99e066d3478 # PsScript High
      type: derived
status: test
description: Detects PowerShell scripts to set the ACL to a file in the Windows folder
references:
    - https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.security/set-acl?view=powershell-5.1
    - https://github.com/redcanaryco/atomic-red-team/blob/74438b0237d141ee9c99747976447dc884cb1a39/atomics/T1505.005/T1505.005.md
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-10-18
tags:
    - attack.stealth
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - OriginalFileName:
              - 'PowerShell.EXE'
              - 'pwsh.dll'
        - Image|endswith:
              - '\powershell.exe'
              - '\pwsh.exe'
    selection_cmdlet:
        CommandLine|contains|all:
            - 'Set-Acl '
            - '-AclObject '
    selection_paths:
        # Note: Add more suspicious paths
        CommandLine|contains:
            - '-Path "C:\Windows'
            - "-Path 'C:\\Windows"
            - '-Path %windir%'
            - '-Path $env:windir'
    selection_permissions:
        # Note: Add more suspicious permissions
        CommandLine|contains:
            - 'FullControl'
            - 'Allow'
    condition: all of selection_*
falsepositives:
    - Unknown
level: high

title: Remote Access Tool - Renamed MeshAgent Execution - MacOS
id: bd3b5eaa-439d-4a42-8f35-a49f5c8a2582
related:
    - id: b471f462-eb0d-4832-be35-28d94bdb4780
      type: similar
    - id: 22c45af6-f590-4d44-bab3-b5b2d2a2b6d9
      type: derived
status: experimental
description: |
    Detects the execution of a renamed instance of the Remote Monitoring and Management (RMM) tool, MeshAgent.
    RMM tools such as MeshAgent are commonly utilized by IT administrators for legitimate remote support and system management.
    However, malicious actors may exploit these tools by renaming them to bypass detection mechanisms, enabling unauthorized access and control over compromised systems.
references:
    - https://www.huntress.com/blog/know-thy-enemy-a-novel-november-case-on-persistent-remote-access
    - https://thecyberexpress.com/ukraine-hit-by-meshagent-malware-campaign/
    - https://wazuh.com/blog/how-to-detect-meshagent-with-wazuh/
    - https://www.security.com/threat-intelligence/medusa-ransomware-attacks
author: Norbert Jaśniewicz (AlphaSOC)
date: 2025-05-19
tags:
    - attack.command-and-control
    - attack.stealth
    - attack.t1219.002
    - attack.t1036.003
logsource:
    category: process_creation
    product: macos
detection:
    selection_meshagent:
        - CommandLine|contains: '--meshServiceName'
        - OriginalFileName|contains: 'meshagent'
    filter_main_legitimate:
        Image|endswith:
            - '/meshagent'
            - '/meshagent_osx64'
    condition: selection_meshagent and not 1 of filter_main_*
falsepositives:
    - Unknown
level: high

title: Suspicious Network Connection to IP Lookup Service APIs
id: edf3485d-dac4-4d50-90e4-b0e5813f7e60
related:
    - id: ec82e2a5-81ea-4211-a1f8-37a0286df2c2
      type: derived
status: test
description: Detects external IP address lookups by non-browser processes via services such as "api.ipify.org". This could be indicative of potential post compromise internet test activity.
references:
    - https://github.com/rsp/scripts/blob/c8bb272d68164a9836e4f273d8f924927f39b8c6/externalip-benchmark.md
    - https://www.cisa.gov/news-events/cybersecurity-advisories/aa20-302a
    - https://thedfirreport.com/2022/11/28/emotet-strikes-again-lnk-file-leads-to-domain-wide-ransomware/
    - https://www.trendmicro.com/en_us/research/23/e/managed-xdr-investigation-of-ducktail-in-trend-micro-vision-one.html
author: Janantha Marasinghe, Nasreddine Bencherchali (Nextron Systems)
date: 2023-04-24
modified: 2024-03-22
tags:
    - attack.discovery
    - attack.t1016
logsource:
    category: network_connection
    product: windows
detection:
    selection:
        - DestinationHostname:
              - 'www.ip.cn'
              - 'l2.io'
        - DestinationHostname|contains:
              - 'api.2ip.ua'
              - 'api.bigdatacloud.net'
              - 'api.ipify.org'
              - 'bot.whatismyipaddress.com'
              - 'canireachthe.net'
              - 'checkip.amazonaws.com'
              - 'checkip.dyndns.org'
              - 'curlmyip.com'
              - 'db-ip.com'
              - 'edns.ip-api.com'
              - 'eth0.me'
              - 'freegeoip.app'
              - 'geoipy.com'
              - 'getip.pro'
              - 'icanhazip.com'
              - 'ident.me'
              - 'ifconfig.io'
              - 'ifconfig.me'
              - 'ip-api.com'
              - 'ip.360.cn'
              - 'ip.anysrc.net'
              - 'ip.taobao.com'
              - 'ip.tyk.nu'
              - 'ipaddressworld.com'
              - 'ipapi.co'
              - 'ipconfig.io'
              - 'ipecho.net'
              - 'ipinfo.io'
              - 'ipip.net'
              - 'ipof.in'
              - 'ipv4.icanhazip.com'
              - 'ipv4bot.whatismyipaddress.com'
              - 'ipv6-test.com'
              - 'ipwho.is'
              - 'jsonip.com'
              - 'myexternalip.com'
              - 'seeip.org'
              - 'wgetip.com'
              - 'whatismyip.akamai.com'
              - 'whois.pconline.com.cn'
              - 'wtfismyip.com'
    filter_optional_brave:
        Image|endswith: '\brave.exe'
    filter_optional_chrome:
        Image:
            - 'C:\Program Files\Google\Chrome\Application\chrome.exe'
            - 'C:\Program Files (x86)\Google\Chrome\Application\chrome.exe'
    filter_optional_firefox:
        Image:
            - 'C:\Program Files\Mozilla Firefox\firefox.exe'
            - 'C:\Program Files (x86)\Mozilla Firefox\firefox.exe'
    filter_optional_ie:
        Image:
            - 'C:\Program Files (x86)\Internet Explorer\iexplore.exe'
            - 'C:\Program Files\Internet Explorer\iexplore.exe'
    filter_optional_maxthon:
        Image|endswith: '\maxthon.exe'
    filter_optional_edge_1:
        - Image|startswith: 'C:\Program Files (x86)\Microsoft\EdgeWebView\Application\'
        - Image|endswith: '\WindowsApps\MicrosoftEdge.exe'
        - Image:
              - 'C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe'
              - 'C:\Program Files\Microsoft\Edge\Application\msedge.exe'
    filter_optional_edge_2:
        Image|startswith:
            - 'C:\Program Files (x86)\Microsoft\EdgeCore\'
            - 'C:\Program Files\Microsoft\EdgeCore\'
        Image|endswith:
            - '\msedge.exe'
            - '\msedgewebview2.exe'
    filter_optional_opera:
        Image|endswith: '\opera.exe'
    filter_optional_safari:
        Image|endswith: '\safari.exe'
    filter_optional_seamonkey:
        Image|endswith: '\seamonkey.exe'
    filter_optional_vivaldi:
        Image|endswith: '\vivaldi.exe'
    filter_optional_whale:
        Image|endswith: '\whale.exe'
    condition: selection and not 1 of filter_optional_*
falsepositives:
    - Legitimate use of the external websites for troubleshooting or network monitoring
level: medium

title: Suspicious permissions modification on a network share
description: Detects scenarios where an attacker modifies network share permissions in order to facilitate lateral movement and avoid detection by creating new network shares
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0005-Defense%20Evasion/T1222.001-File%20and%20Directory%20Permissions%20Modification
- https://medium.com/falconforce/falconfriday-monitoring-for-public-shares-0xff1a-ece14fe137e1
tags:
- attack.defense_evasion
- attack.t1222.001
- attack.lateral_movement
- attack.t1021.002
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  service: security
detection:
  selection:
    EventID: 5143  # modified share
    #OldSD != NewSD # Comparing 2 fields is not possible in SIGMA language
  filter:
    Computer: '%domain_controllers%'
  condition: selection and not filter
falsepositives:
- Administrator modification on network shares, SCCM servers, DFS shares, printer servers
level: medium

title: Suspicious Process Patterns NTDS.DIT Exfil
id: 8bc64091-6875-4881-aaf9-7bd25b5dda08
status: test
description: Detects suspicious process patterns used in NTDS.DIT exfiltration
references:
    - https://www.ired.team/offensive-security/credential-access-and-credential-dumping/ntds.dit-enumeration
    - https://www.n00py.io/2022/03/manipulating-user-passwords-without-mimikatz/
    - https://pentestlab.blog/tag/ntds-dit/
    - https://github.com/samratashok/nishang/blob/414ee1104526d7057f9adaeee196d91ae447283e/Gather/Copy-VSS.ps1
    - https://github.com/zcgonvh/NTDSDumpEx
    - https://github.com/rapid7/metasploit-framework/blob/d297adcebb5c1df6fe30b12ca79b161deb71571c/data/post/powershell/NTDSgrab.ps1
    - https://blog.talosintelligence.com/2022/08/recent-cyber-attack.html?m=1
author: Florian Roth (Nextron Systems)
date: 2022-03-11
modified: 2022-11-10
tags:
    - attack.credential-access
    - attack.t1003.003
logsource:
    product: windows
    category: process_creation
detection:
    selection_tool:
        # https://github.com/zcgonvh/NTDSDumpEx
        - Image|endswith:
              - '\NTDSDump.exe'
              - '\NTDSDumpEx.exe'
        - CommandLine|contains|all:
              # ntdsdumpex.exe -d ntds.dit -o hash.txt -s system.hiv
              - 'ntds.dit'
              - 'system.hiv'
        - CommandLine|contains: 'NTDSgrab.ps1'
    selection_oneliner_1:
        # powershell "ntdsutil.exe 'ac i ntds' 'ifm' 'create full c:\temp' q q"
        CommandLine|contains|all:
            - 'ac i ntds'
            - 'create full'
    selection_onliner_2:
        # cmd.exe /c copy z:\windows\ntds\ntds.dit c:\exfil\ntds.dit
        CommandLine|contains|all:
            - '/c copy '
            - '\windows\ntds\ntds.dit'
    selection_onliner_3:
        # ntdsutil "activate instance ntds" "ifm" "create full c:\windows\temp\data\" "quit" "quit"
        CommandLine|contains|all:
            - 'activate instance ntds'
            - 'create full'
    selection_powershell:
        CommandLine|contains|all:
            - 'powershell'
            - 'ntds.dit'
    set1_selection_ntds_dit:
        CommandLine|contains: 'ntds.dit'
    set1_selection_image_folder:
        - ParentImage|contains:
              - '\apache'
              - '\tomcat'
              - '\AppData\'
              - '\Temp\'
              - '\Public\'
              - '\PerfLogs\'
        - Image|contains:
              - '\apache'
              - '\tomcat'
              - '\AppData\'
              - '\Temp\'
              - '\Public\'
              - '\PerfLogs\'
    condition: 1 of selection* or all of set1*
falsepositives:
    - Unknown
level: high
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_susp_ntds/info.yml

title: Tamper Windows Defender - ScriptBlockLogging
id: 14c71865-6cd3-44ae-adaa-1db923fae5f2
related:
    - id: ec19ebab-72dc-40e1-9728-4c0b805d722c
      type: derived
status: test
description: Detects PowerShell scripts attempting to disable scheduled scanning and other parts of Windows Defender ATP or set default actions to allow.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1562.001/T1562.001.md
    - https://learn.microsoft.com/en-us/powershell/module/defender/set-mppreference?view=windowsserver2022-ps
    - https://bidouillesecurity.com/disable-windows-defender-in-powershell/
author: frack113, elhoim, Tim Shelton (fps, alias support), Swachchhanda Shrawan Poudel, Nasreddine Bencherchali (Nextron Systems)
date: 2022-01-16
modified: 2024-01-02
tags:
    - attack.defense-impairment
    - attack.t1685
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection_options_disabling_preference:
        ScriptBlockText|contains: 'Set-MpPreference'
    selection_options_disabling_function:
        ScriptBlockText|contains:
            - '-dbaf $true'
            - '-dbaf 1'
            - '-dbm $true'
            - '-dbm 1'
            - '-dips $true'
            - '-dips 1'
            - '-DisableArchiveScanning $true'
            - '-DisableArchiveScanning 1'
            - '-DisableBehaviorMonitoring $true'
            - '-DisableBehaviorMonitoring 1'
            - '-DisableBlockAtFirstSeen $true'
            - '-DisableBlockAtFirstSeen 1'
            - '-DisableCatchupFullScan $true'
            - '-DisableCatchupFullScan 1'
            - '-DisableCatchupQuickScan $true'
            - '-DisableCatchupQuickScan 1'
            - '-DisableIntrusionPreventionSystem $true'
            - '-DisableIntrusionPreventionSystem 1'
            - '-DisableIOAVProtection $true'
            - '-DisableIOAVProtection 1'
            - '-DisableRealtimeMonitoring $true'
            - '-DisableRealtimeMonitoring 1'
            - '-DisableRemovableDriveScanning $true'
            - '-DisableRemovableDriveScanning 1'
            - '-DisableScanningMappedNetworkDrivesForFullScan $true'
            - '-DisableScanningMappedNetworkDrivesForFullScan 1'
            - '-DisableScanningNetworkFiles $true'
            - '-DisableScanningNetworkFiles 1'
            - '-DisableScriptScanning $true'
            - '-DisableScriptScanning 1'
            - '-MAPSReporting $false'
            - '-MAPSReporting 0'
            - '-drdsc $true'
            - '-drdsc 1'
            - '-drtm $true'
            - '-drtm 1'
            - '-dscrptsc $true'
            - '-dscrptsc 1'
            - '-dsmndf $true'
            - '-dsmndf 1'
            - '-dsnf $true'
            - '-dsnf 1'
            - '-dss $true'
            - '-dss 1'
    selection_other_default_actions_allow:
        ScriptBlockText|contains: 'Set-MpPreference'
    selection_other_default_actions_func:
        ScriptBlockText|contains:
            - 'HighThreatDefaultAction Allow'
            - 'htdefac Allow'
            - 'LowThreatDefaultAction Allow'
            - 'ltdefac Allow'
            - 'ModerateThreatDefaultAction Allow'
            - 'mtdefac Allow'
            - 'SevereThreatDefaultAction Allow'
            - 'stdefac Allow'
    condition: all of selection_options_disabling_* or all of selection_other_default_actions_*
falsepositives:
    - Legitimate PowerShell scripts that disable Windows Defender for troubleshooting purposes. Must be investigated.
level: high
regression_tests_path: regression_data/rules/windows/powershell/powershell_script/posh_ps_tamper_windows_defender_set_mp/info.yml