Detection rules › Sigma

Windows Recovery Environment Disabled Via Reagentc

Severity
medium
Author
Daniel Koifman (KoifSec), Michael Vilshin
Source
upstream

Detects attempts to disable windows recovery environment using Reagentc. ReAgentc.exe is a command-line tool in Windows used to manage the Windows Recovery Environment (WinRE). It allows users to enable, disable, and configure WinRE, which is used for troubleshooting and repairing common boot issues.

MITRE ATT&CK coverage

TacticTechniques
ImpactT1490 Inhibit System Recovery

Event coverage

ProviderEvent IDTitle
Sysmon1Process creation

Stages and Predicates

Stage 1: all of selection_img

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

Stage 2: all of selection_cli

CommandLine|contains: '/disable'

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
  • /disable corpus 2 (sigma 2)
Imageends_with
  • \reagentc.exe
OriginalFileNameeq
  • reagentc.exe