Rundll32 with no Command Line Arguments with Network
The following analytic detects the execution of rundll32.exe without command line arguments, followed by a network connection. This behavior is identified using Endpoint Detection and Response (EDR) telemetry and…
Description
The following analytic detects the execution of rundll32.exe without command line arguments, followed by a network connection. This behavior is identified using Endpoint Detection and Response (EDR) telemetry and network traffic data. It is significant because rundll32.exe typically requires arguments to function, and its absence is often associated with malicious activity, such as Cobalt Strike. If confirmed malicious, this activity could indicate an attempt to establish unauthorized network connections, potentially leading to data exfiltration or further compromise of the system.
Detection logic
Detection requirements
- Platform
- Windows
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- sysmon_eventid_1_and_sysmon_eventid_3
Known benign triggers
- Although unlikely, some legitimate applications may use a moved copy of rundll32, triggering a false positive.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| attack.mitre.org/techniques/T1218/011/ | 9 |
| bohops.com/2018/02/26/leveraging-inf-sct-fetch-execute-techniques-for-bypass-evasion-persistence/ | 4 |
| github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1218.011/T1218.011.md | 5 |
| lolbas-project.github.io/lolbas/Binaries/Rundll32/ | 7 |
From the source
- At source
- Open at source
- Upstream identifier
- 35307032-a12d-11eb-835f-acde48001122
- Tagged by the source as
- BlackByte RansomwareBlackSuit RansomwareCactus RansomwareCobalt StrikeCompromised Windows HostGraceful Wipe Out AttackPrintNightmare CVE-2021-34527Suspicious Rundll32 ActivityEndpointendpointSplunk CloudSplunk EnterpriseSplunk Enterprise Securityendpoint
Licence
- Published under
- Apache License 2.0Read the licence
- Attribution
- Required
- Obtained under
- Apache-2.0Read the origin licence
Authorship
- Written by
- Published
- Aug 26, 2026
- Version
- 1