Suspicious Winlogon Loading Keyboard Layout DLL kbdus1.dll

ATT&CK techniques

Persistence → Priv Esc

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1547.004Winlogon Helper DLL
Priv Esc
- T1547.004Winlogon Helper DLL
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects winlogon.exe loading a DLL named kbdus1.dll, a keyboard-layout persistence technique used by Backdoor.Stupig to execute code as SYSTEM at logon. The legitimate keyboard file is kbdus.dll without the trailing digit.

Reporting behind it

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Suspicious Winlogon Loading Keyboard Layout DLL kbdus1.dll

Pivot detection · T1547.004 · 7 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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