Rundll32.exe executes a rare unsigned module

Synopsis

Field	Value
Activation Period	14 Days
Training Period	30 Days
Test Period	N/A (single event)
Deduplication Period	1 Day
Required Data	XDR Agent
Detector Tags	LOLBIN Execution Analytics
ATT&CK Tactic	Stealth (TA0005)
ATT&CK Technique	System Binary Proxy Execution: Rundll32 (T1218.011)
Severity	Low

Description

Rundll32.exe executes a rare unsigned module, which can indicate an attacker's malicious execution.

Attacker's Goals

Evading detections by running code from a signed Microsoft executable.

Investigative actions

Check whether the loaded module with the corresponding hash is benign and if this was a desired behavior as part of its normal execution flow.

Variations

Rundll32.exe executes a rare unsigned module with very high entropy

Synopsis

Field	Value
ATT&CK Tactic	Stealth (TA0005)
ATT&CK Technique	System Binary Proxy Execution: Rundll32 (T1218.011)
Severity	Medium

Description

Rundll32.exe executes a rare unsigned module, which can indicate an attacker's malicious execution. The module executed by Rundll32 has very high entropy.

Attacker's Goals

Evading detections by running code from a signed Microsoft executable.

Investigative actions

Check whether the loaded module with the corresponding hash is benign and if this was a desired behavior as part of its normal execution flow.

Rundll32.exe executes a rare unsigned module with suspicious characteristics

Synopsis

Field	Value
ATT&CK Tactic	Stealth (TA0005)
ATT&CK Technique	System Binary Proxy Execution: Rundll32 (T1218.011)
Severity	Medium

Description

Rundll32.exe executes a rare unsigned module, which can indicate an attacker's malicious execution.

Attacker's Goals

Evading detections by running code from a signed Microsoft executable.

Investigative actions

Check whether the loaded module with the corresponding hash is benign and if this was a desired behavior as part of its normal execution flow.