Malicious Scriptlet Execution via regsvr32

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.exe registering a remote or scriptlet-backed COM object, the Squiblydoo living-off-the-land technique for executing attacker code through a signed binary. Adversaries use scrobj.dll with remote .sct scriptlets to run arbitrary script while bypassing application allowlisting.

Reporting behind it

Related detections9 linkedT1218.010 — drag to rearrange

Suspicious Office Application Spawning Regsvr32 via Process Chain (via process_creation)

Suspicious Script Host Spawning Regsvr32 via Strela Stealer JScript Loader (via process_creation)

Malicious DLL Registration via regsvr32 Loading prnfldr (via process_creation)

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

Suspicious regsvr32 Registering DLL from User AppData

Malicious Regsvr32 Loading Masqueraded VPN DLL via Process Creation

Malicious Scriptlet Execution via regsvr32

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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