Detection rules › Elastic

Potential Privileged Escalation via SamAccountName Spoofing

Author
Elastic
Source
upstream

Identifies a suspicious computer account name rename event, which may indicate an attempt to exploit CVE-2021-42278 to elevate privileges from a standard domain user to a user with domain admin privileges. CVE-2021-42278 is a security vulnerability that allows potential attackers to impersonate a domain controller via samAccountName attribute spoofing.

MITRE ATT&CK coverage

TacticTechniques
Initial AccessT1078 Valid Accounts, T1078.002 Valid Accounts: Domain Accounts
PersistenceT1078 Valid Accounts, T1078.002 Valid Accounts: Domain Accounts, T1098 Account Manipulation
Privilege EscalationT1068 Exploitation for Privilege Escalation, T1078 Valid Accounts, T1078.002 Valid Accounts: Domain Accounts, T1098 Account Manipulation
Defense EvasionT1036 Masquerading, T1078 Valid Accounts, T1078.002 Valid Accounts: Domain Accounts

Event coverage

ProviderEvent IDTitle
Security-Auditing4781The name of an account was changed.

Stages and Predicates

Stage 1: eql:iam

not winlog.event_data.NewTargetUserName:"*$" and event.action:"renamed-user-account" and winlog.event_data.OldTargetUserName:"*$"

Exclusions

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

StageFieldKindExcluded values
1NewTargetUserNameends_with$

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
event.actioneq
  • renamed-user-account
winlog.event_data.OldTargetUserNamewildcard
  • *$