Malicious DLL Registration via regsvr32 Loading prnfldr (via process_creation)

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 the prnfldr.dll payload using the silent install flags. In Operation Phantom Net Voxel APT28 executes its loader DLL through regsvr32 with the /n /i options to run code while bypassing application controls. Regsvr32 loading this named DLL is characteristic of the campaign proxy execution.

Reporting behind it

Related detections9 linkedT1218.010 — drag to rearrange

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Suspicious regsvr32 Registering DLL from User AppData

Malicious Regsvr32 Loading Masqueraded VPN DLL via Process Creation

Malicious Regsvr32 ShellExec_RunDLL Proxy Execution (via process_creation)

Suspicious DLL Execution via Regsvr32 DllInstall of dat File

Malicious Xctdoor XcLoader Execution via Regsvr32 AppX Path Abuse (via process_creation)

Malicious DLL Registration via regsvr32 Loading prnfldr (via process_creation)

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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