Detection rules › Sigma

UAC Bypass Tools Using ComputerDefaults

Severity
high
Author
Christian Burkard (Nextron Systems)
Source
upstream

Detects tools such as UACMe used to bypass UAC with computerdefaults.exe (UACMe 59)

MITRE ATT&CK coverage

TacticTechniques
Privilege EscalationT1548.002 Abuse Elevation Control Mechanism: Bypass User Account Control
Defense EvasionT1548.002 Abuse Elevation Control Mechanism: Bypass User Account Control

Event coverage

ProviderEvent IDTitle
Sysmon1Process creation
Security-Auditing4688A new process has been created.

Stages and Predicates

Stage 1: selection

IntegrityLevel: [High, S-1-16-12288, S-1-16-16384, System]
Image: 'C:\Windows\System32\ComputerDefaults.exe'

Stage 2: not filter

or:
ParentImage|contains: ':\Program Files'
ParentImage|contains: ':\Windows\System32'

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
Imageeq
  • C:\Windows\System32\ComputerDefaults.exe
IntegrityLeveleq
  • High corpus 16 (sigma 16)
  • S-1-16-12288 corpus 16 (sigma 16)
  • S-1-16-16384 corpus 21 (sigma 21)
  • System corpus 21 (sigma 21)
ParentImagematch
  • :\Program Files
  • :\Windows\System32