Sigma Rule Library

SNAKE Malware WerFault Persistence File Creation

Detects the creation of a file named "WerFault.exe" in the WinSxS directory by a non-system process, which can be indicative of potential SNAKE malware activity

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Detection logic

selection

TargetFilename|startswith: C:\Windows\WinSxS\
TargetFilename|endswith: \WerFault.exe

filter_main_system_location

Image|startswith:
  - C:\Windows\System32\
  - C:\Windows\SysWOW64\
  - C:\Windows\WinSxS\

Condition

selection and not 1 of filter_main_*

Raw YAML

title: SNAKE Malware WerFault Persistence File Creation
id: 64827580-e4c3-4c64-97eb-c72325d45399
status: test
description: Detects the creation of a file named "WerFault.exe" in the WinSxS directory by a non-system process, which can be indicative of potential SNAKE malware activity
references:
    - https://media.defense.gov/2023/May/09/2003218554/-1/-1/0/JOINT_CSA_HUNTING_RU_INTEL_SNAKE_MALWARE_20230509.PDF
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-05-10
modified: 2023-05-18
tags:
    - attack.execution
    - detection.emerging-threats
logsource:
    category: file_event
    product: windows
detection:
    selection:
        TargetFilename|startswith: 'C:\Windows\WinSxS\'
        TargetFilename|endswith: '\WerFault.exe'
    filter_main_system_location:
        Image|startswith:
            - 'C:\Windows\System32\'
            - 'C:\Windows\SysWOW64\'
            - 'C:\Windows\WinSxS\'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: high

False positives

  • Unknown

References

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