Sigma Rule Library

REvil Kaseya Incident Malware Patterns

Detects process command line patterns and locations used by REvil group in Kaseya incident (can also match on other malware)

View on GitHubOpen raw file

Detection logic

selection1

CommandLine|contains:
  - C:\Windows\cert.exe
  - del /q /f c:\kworking\agent.crt
  - Kaseya VSA Agent Hot-fix
  - \AppData\Local\Temp\MsMpEng.exe
  - rmdir /s /q %SystemDrive%\inetpub\logs
  - del /s /q /f %SystemDrive%\\*.log
  - c:\kworking1\agent.exe
  - c:\kworking1\agent.crt

selection2

Image:
  - C:\Windows\MsMpEng.exe
  - C:\Windows\cert.exe
  - C:\kworking\agent.exe
  - C:\kworking1\agent.exe

selection3

CommandLine|contains|all:
  - del /s /q /f
  - WebPages\Errors\webErrorLog.txt

Condition

1 of selection*

Raw YAML

title: REvil Kaseya Incident Malware Patterns
id: 5de632bc-7fbd-4c8a-944a-fce55c59eae5
status: test
description: Detects process command line patterns and locations used by REvil group in Kaseya incident (can also match on other malware)
references:
    - https://community.sophos.com/b/security-blog/posts/active-ransomware-attack-on-kaseya-customers
    - https://www.joesandbox.com/analysis/443736/0/html
    - https://doublepulsar.com/kaseya-supply-chain-attack-delivers-mass-ransomware-event-to-us-companies-76e4ec6ec64b
    - https://therecord.media/revil-ransomware-executes-supply-chain-attack-via-malicious-kaseya-update/
    - https://blog.truesec.com/2021/07/04/kaseya-supply-chain-attack-targeting-msps-to-deliver-revil-ransomware/
author: Florian Roth (Nextron Systems)
date: 2021-07-03
modified: 2022-05-20
tags:
    - attack.execution
    - attack.t1059
    - attack.g0115
    - detection.emerging-threats
logsource:
    category: process_creation
    product: windows
detection:
    selection1:
        CommandLine|contains:
            - 'C:\Windows\cert.exe'
            - 'del /q /f c:\kworking\agent.crt'
            - 'Kaseya VSA Agent Hot-fix'
            - '\AppData\Local\Temp\MsMpEng.exe'
            - 'rmdir /s /q %SystemDrive%\inetpub\logs'
            - 'del /s /q /f %SystemDrive%\\*.log'
            - 'c:\kworking1\agent.exe'
            - 'c:\kworking1\agent.crt'
    selection2:
        Image:
            - 'C:\Windows\MsMpEng.exe'
            - 'C:\Windows\cert.exe'
            - 'C:\kworking\agent.exe'
            - 'C:\kworking1\agent.exe'
    selection3:
        CommandLine|contains|all:
            - 'del /s /q /f'
            - 'WebPages\Errors\webErrorLog.txt'
    condition: 1 of selection*
falsepositives:
    - Unknown
level: critical

False positives

  • Unknown

References

Similar rules