IMPORTANT: No additional bug fixes or documentation updates
will be released for this version. For the latest information, see the
current release documentation.
Untrusted DLL Loaded by Azure AD Sync Service
editUntrusted DLL Loaded by Azure AD Sync Service
editIdentifies the load of a DLL without a valid code signature by the Azure AD Sync process, which may indicate an attempt to persist or collect sensitive credentials passing through the Azure AD synchronization server.
Rule type: eql
Rule indices:
- winlogbeat-*
- logs-endpoint.events.library*
- logs-windows.sysmon_operational-*
Severity: high
Risk score: 73
Runs every: 5m
Searches indices from: now-9m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References:
Tags:
- Domain: Endpoint
- OS: Windows
- Use Case: Threat Detection
- Tactic: Credential Access
- Data Source: Elastic Defend
- Data Source: Sysmon
Version: 1
Rule authors:
- Elastic
- Matteo Potito Giorgio
Rule license: Elastic License v2
Rule query
editany where host.os.type == "windows" and process.name : "AzureADConnectAuthenticationAgentService.exe" and
(
(event.category == "library" and event.action == "load") or
(event.category == "process" and event.action : "Image loaded*")
) and
not (?dll.code_signature.trusted == true or file.code_signature.status == "Valid") and not
(
/* Elastic defend DLL path */
?dll.path :
("?:\\Windows\\assembly\\NativeImages*",
"?:\\Windows\\Microsoft.NET\\*",
"?:\\Windows\\WinSxS\\*",
"?:\\Windows\\System32\\DriverStore\\FileRepository\\*") or
/* Sysmon DLL path is mapped to file.path */
file.path :
("?:\\Windows\\assembly\\NativeImages*",
"?:\\Windows\\Microsoft.NET\\*",
"?:\\Windows\\WinSxS\\*",
"?:\\Windows\\System32\\DriverStore\\FileRepository\\*")
)
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Credential Access
- ID: TA0006
- Reference URL: https://attack.mitre.org/tactics/TA0006/
-
Technique:
- Name: OS Credential Dumping
- ID: T1003
- Reference URL: https://attack.mitre.org/techniques/T1003/