Sigma rule: UNC4841 - Potential SEASPY Execution

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-b2dfe8e7678d, updated 2023-06-16T00:00:00.000Z.

Rule

Title
UNC4841 - Potential SEASPY Execution
Status
test
Level
critical
Author
Nasreddine Bencherchali (Nextron Systems)
Date
2023-06-16
File
rules-emerging-threats/2023/TA/UNC4841-Barracuda-ESG-Zero-Day-Exploitation/proc_creation_lnx_atp_unc4841_seaspy_execution.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects execution of specific named binaries which were used by UNC4841 to deploy their SEASPY backdoor

Log source

product
linux
category
process_creation

Detection

selection:
    Image|endswith:
        - '/BarracudaMailService'
        - '/resize2fstab'
        - '/resize_reisertab'
condition: selection

False positives (as the rule lists them)

  • Unlikely

Tags

  • attack.execution
  • detection.emerging-threats

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-emerging-threats/2023/TA/UNC4841-Barracuda-ESG-Zero-Day-Exploitation/proc_creation_lnx_atp_unc4841_seaspy_execution.yml

Sources and licences

  • SigmaHQ

    "UNC4841 - Potential SEASPY Execution" by Nasreddine Bencherchali (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules-emerging-threats/2023/TA/UNC4841-Barracuda-ESG-Zero-Day-Exploitation/proc_creation_lnx_atp_unc4841_seaspy_execution.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: UNC4841 - Potential SEASPY Execution",
entity page, dataset version ref-b2dfe8e7678d, updated 2023-06-16T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/f6a711f3-d032-4f9e-890b-bbe776236c84 (accessed 2026-11-03).
Underlying source: SigmaHQ rule f6a711f3-d032-4f9e-890b-bbe776236c84, 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.