Detection rules › Elastic

Active Directory Group Modification by SYSTEM

Author
Elastic
Source
upstream

Identifies a user being added to an active directory group by the SYSTEM (S-1-5-18) user. This behavior can indicate that the attacker has achieved SYSTEM privileges in a domain controller, which attackers can obtain by exploiting vulnerabilities or abusing default group privileges (e.g., Server Operators), and is attempting to pivot to a domain account.

MITRE ATT&CK coverage

TacticTechniques
PersistenceT1098 Account Manipulation
Privilege EscalationT1098 Account Manipulation

Event coverage

ProviderEvent IDTitle
Security-Auditing4728A member was added to a security-enabled global group.

Stages and Predicates

Stage 1: eql:iam

not group.id:"S-1-5-21-*-513" and winlog.event_data.SubjectUserSid:"S-1-5-18"

Exclusions

Top-level NOT(...) conjuncts — predicates this rule actively suppresses.

StageFieldKindExcluded values
1group.idwildcardS-1-5-21-*-513

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
winlog.event_data.SubjectUserSidwildcard
  • S-1-5-18