Detection rules › Sigma

RunMRU Registry Key Deletion

Severity
high
Author
Swachchhanda Shrawan Poudel (Nextron Systems)
Source
upstream

Detects deletion of the RunMRU registry key, which stores the history of commands executed via the Run dialog. In the clickfix techniques, the phishing lures instruct users to open a run dialog through (Win + R) and execute malicious commands. Adversaries may delete this key to cover their tracks after executing commands.

MITRE ATT&CK coverage

TacticTechniques
Defense EvasionT1070.003 Indicator Removal: Clear Command History

Event coverage

ProviderEvent IDTitle
Sysmon1Process creation

Stages and Predicates

Stage 1: all of selection_img

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

Stage 2: all of selection_cli

CommandLine|contains: ' del'
CommandLine|contains: '\Software\Microsoft\Windows\CurrentVersion\Explorer\RunMRU'

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
  • del
  • \Software\Microsoft\Windows\CurrentVersion\Explorer\RunMRU
Imageends_with
  • \reg.exe corpus 46 (sigma 46)
OriginalFileNameeq
  • reg.exe corpus 29 (sigma 29)