Sigma rule: Dllhost.EXE Execution Anomaly

Rule

Title

Dllhost.EXE Execution Anomaly

Status

test

Level

high

Author

Nasreddine Bencherchali (Nextron Systems)

Date

2022-06-27

Modified

2023-05-15

File

rules/windows/process_creation/proc_creation_win_dllhost_no_cli_execution.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects a "dllhost" process spawning with no commandline arguments which is very rare to happen and could indicate process injection activity or malware mimicking similar system processes.

Log source

product

windows

category

process_creation

Detection

selection:
    Image|endswith: '\dllhost.exe'
    CommandLine:
        - 'dllhost.exe'
        - 'dllhost'
filter_main_null:
    CommandLine: null
condition: selection and not 1 of filter_main_*

False positives (as the rule lists them)

• Unlikely

Tags

• attack.privilege-escalation
• attack.stealth
• attack.t1055

MITRE ATT&CK ids this rule names

• T1055

References

• https://redcanary.com/blog/child-processes/
• https://nasbench.medium.com/what-is-the-dllhost-exe-process-actually-running-ef9fe4c19c08
• https://www.ncsc.gov.uk/static-assets/documents/malware-analysis-reports/goofy-guineapig/NCSC-MAR-Goofy-Guineapig.pdf

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_dllhost_no_cli_execution.yml