Detection rules › Sigma

UAC Bypass Using Windows Media Player - File

Severity
high
Author
Christian Burkard (Nextron Systems)
Source
upstream

Detects the pattern of UAC Bypass using Windows Media Player osksupport.dll (UACMe 32)

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
Sysmon11FileCreate

Stages and Predicates

Stage 1: 1 of selection1

TargetFilename|endswith: '\AppData\Local\Temp\OskSupport.dll'
TargetFilename|startswith: 'C:\Users\'

Stage 2: 1 of selection2

Image: 'C:\Windows\system32\DllHost.exe'
TargetFilename: 'C:\Program Files\Windows Media Player\osk.exe'

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\DllHost.exe
TargetFilenameends_with
  • \AppData\Local\Temp\OskSupport.dll
TargetFilenameeq
  • C:\Program Files\Windows Media Player\osk.exe
TargetFilenamestarts_with
  • C:\Users\ corpus 12 (sigma 12)