Detection rules › Sigma

Potential ReflectDebugger Content Execution Via WerFault.EXE

Severity
medium
Author
X__Junior (Nextron Systems)
Source
upstream

Detects execution of "WerFault.exe" with the "-pr" commandline flag that is used to run files stored in the ReflectDebugger key which could be used to store the path to the malware in order to masquerade the execution flow

MITRE ATT&CK coverage

TacticTechniques
Defense EvasionT1036 Masquerading

Event coverage

ProviderEvent IDTitle
Sysmon1Process creation

Stages and Predicates

Stage 1: all of selection_img

or:
Image|endswith: '\WerFault.exe'
OriginalFileName: WerFault.exe

Stage 2: all of selection_cli

CommandLine|contains: ' -pr '

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
  • -pr
Imageends_with
  • \WerFault.exe corpus 8 (sigma 8)
OriginalFileNameeq
  • WerFault.exe corpus 3 (sigma 3)