Suspicious regsvr32 Registering DLL from User AppData

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1218.010Regsvr32
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects regsvr32 registering a DLL located in a user AppData path. In More_eggs intrusions a WMI launched process fetched a numbered dll that regsvr32 then registered to load the backdoor. Executing DLLs from user writable directories via regsvr32 is a common proxy execution technique for staged malware.

Reporting behind it

Related detections9 linkedT1218.010 — drag to rearrange

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Suspicious Regsvr32 Execution of SafePay Loader DLL

Suspicious Scheduled Task Running Regsvr32 with Extreme Duration by StaryDobry

Malicious DynamicWrapperX Registration via regsvr32 (via process_creation)

Suspicious Run Key Persistence Executing regsvr32

Malicious Regsvr32 Loading Masqueraded VPN DLL via Process Creation

Suspicious regsvr32 Registering DLL from User AppData

Pivot detection · T1218.010 · 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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