Sigma rule: Uncommon Network Connection Initiated By Certutil.EXE

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-1f7362bc36e1, updated 2024-05-31T00:00:00.000Z.

Rule

Title
Uncommon Network Connection Initiated By Certutil.EXE
Status
test
Level
high
Author
frack113, Florian Roth (Nextron Systems)
Date
2022-09-02
Modified
2024-05-31
File
rules/windows/network_connection/net_connection_win_certutil_initiated_connection.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects a network connection initiated by the certutil.exe utility.
Attackers can abuse the utility in order to download malware or additional payloads.

Log source

product
windows
category
network_connection

Detection

selection:
    Image|endswith: '\certutil.exe'
    Initiated: 'true'
    DestinationPort:
        - 80
        - 135
        - 443
        - 445
condition: selection

False positives (as the rule lists them)

  • Unknown

Tags

  • attack.command-and-control
  • attack.t1105

MITRE ATT&CK ids this rule names

References

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/network_connection/net_connection_win_certutil_initiated_connection.yml

Sources and licences

  • SigmaHQ

    "Uncommon Network Connection Initiated By Certutil.EXE" by frack113, Florian Roth (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/network_connection/net_connection_win_certutil_initiated_connection.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Uncommon Network Connection Initiated By Certutil.EXE",
entity page, dataset version ref-1f7362bc36e1, updated 2024-05-31T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/0dba975d-a193-4ed1-a067-424df57570d1 (accessed 2026-11-03).
Underlying source: SigmaHQ rule 0dba975d-a193-4ed1-a067-424df57570d1, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.