Detection rules › Sigma

Microsoft Defender service deactivation attempt (command)

Status
experimental
Severity
high
Log source
product windows, category process_creation
Author
mdecrevoisier
Source
github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker attempts to disable Defender security service. If tamper protection is enabled, this action may not work.

MITRE ATT&CK coverage

Event coverage

Rule body yaml

title: Microsoft Defender service deactivation attempt (command)
description: Detects scenarios where an attacker attempts to disable Defender security service. If tamper protection is enabled, this action may not work.
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0005-Defense%20Evasion/T1562.001-Impair%20Defenses-Disable%20or%20Modify%20tool
- https://github.com/swagkarna/Defeat-Defender-V1.2
- https://docs.microsoft.com/en-us/microsoft-365/security/defender-endpoint/microsoft-defender-antivirus-on-windows-server?view=o365-worldwide
tags:
- attack.defense_evasion
- attack.t1562.001
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  category: process_creation
detection:
  selection:
    NewProcessName|endswith: '\sc.exe'
    CommandLine|contains|all:
      - sc
      - config
      - disabled
    CommandLine|contains: # Defender related services names
      - WinDefend
      - Sense
      - MpsSvc
  condition: selection
falsepositives:
- None
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
  NewProcessName|endswith: '\sc.exe'
  CommandLine|contains|all:
    - sc
    - config
    - disabled
  CommandLine|contains:
    - WinDefend
    - Sense
    - MpsSvc

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
CommandLinematch
  • MpsSvc corpus 2 (sigma 2)
  • Sense corpus 2 (sigma 2)
  • WinDefend corpus 4 (sigma 3, kusto 1)
  • config corpus 16 (sigma 15, splunk 1)
  • disabled corpus 6 (sigma 5, splunk 1)
  • sc corpus 6 (sigma 6)
NewProcessNameends_with
  • \sc.exe corpus 30 (sigma 30)