Detection rules › Sigma

System Language Discovery via Reg.Exe

Severity
medium
Author
Marco Pedrinazzi (@pedrinazziM) (InTheCyber)
Source
upstream

Detects the usage of Reg.Exe to query system language settings. Attackers may discover the system language to determine the geographic location of victims, customize payloads for specific regions, or avoid targeting certain locales to evade detection.

MITRE ATT&CK coverage

TacticTechniques
DiscoveryT1614.001 System Location Discovery: System Language Discovery

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: 'Control\Nls\Language'
CommandLine|contains: query

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
  • Control\Nls\Language
  • query corpus 6 (sigma 6)
Imageends_with
  • \reg.exe corpus 46 (sigma 46)
OriginalFileNameeq
  • reg.exe corpus 29 (sigma 29)