Detection rules › Sigma

Potential Persistence Via LSA Extensions

Severity
high
Author
Nasreddine Bencherchali (Nextron Systems)
Source
upstream

Detects when an attacker modifies the "REG_MULTI_SZ" value named "Extensions" to include a custom DLL to achieve persistence via lsass. The "Extensions" list contains filenames of DLLs being automatically loaded by lsass.exe. Each DLL has its InitializeLsaExtension() method called after loading.

Event coverage

ProviderEvent IDTitle
Sysmon13RegistryEvent (Value Set)

Stages and Predicates

Stage 1: selection

TargetObject|contains: '\SYSTEM\CurrentControlSet\Control\LsaExtensionConfig\LsaSrv\Extensions'

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
TargetObjectmatch
  • \SYSTEM\CurrentControlSet\Control\LsaExtensionConfig\LsaSrv\Extensions