Suspicious SmallTiger Backdoor DLL Load via Image Load

ATT&CK techniques

Priv Esc → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
- T1055Process Injection
Defense Evasion
- T1055Process Injection
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects the load of SmallTiger.dll, the named backdoor DLL used by the North Korean actor Onyx Sleet to establish access on compromised hosts. The DLL is delivered and side-loaded during intrusions, so its presence in an image load event is a strong indicator of Onyx Sleet activity.

Reporting behind it

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Suspicious SmallTiger Backdoor DLL Load via Image Load

Pivot detection · T1055 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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