Potential Access Token Abuse

Severity: medium
Author: Michaela Adams, Zach Mathis
Source: upstream

Detects potential token impersonation and theft. Example, when using "DuplicateToken(Ex)" and "ImpersonateLoggedOnUser" with the "LOGON32_LOGON_NEW_CREDENTIALS flag".

MITRE ATT&CK coverage

Tactic	Techniques
Privilege Escalation	`T1134.001` Access Token Manipulation: Token Impersonation/Theft
Defense Evasion	`T1134.001` Access Token Manipulation: Token Impersonation/Theft

Event coverage

Provider	Event ID	Title
Security-Auditing	4624	An account was successfully logged on.

Stages and Predicates

Stage 1: `selection`

AuthenticationPackageName: Negotiate
ImpersonationLevel: '%%1833'
LogonProcessName: Advapi
LogonType: 9

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.

Field	Kind	Values
`AuthenticationPackageName`	eq	`Negotiate` corpus 3 (sigma 3)
`ImpersonationLevel`	eq	`%%1833`
`LogonProcessName`	eq	`Advapi`
`LogonType`	eq	`9` corpus 5 (sigma 5)

Neighbors

Broader alternatives (more inclusive than this rule)

These rules match a superset of what this rule catches. They cover the same events plus more. Use them if you want wider coverage and can absorb more false positives.

Potential Account Takeover - Mixed Logon Types [elastic] (cross-vendor) (drops 4 filters this rule applies) (first-stage match only; downstream stages may differ)
Potential Account Takeover - Logon from New Source IP [elastic] (cross-vendor) (drops 4 filters this rule applies) (first-stage match only; downstream stages may differ)
Outgoing Logon with New Credentials [sigma] (drops 3 filters this rule applies)