Script Interpreter Spawning Credential Scanner - Linux — Sigma Rule

Rule metadata and linked tags

Author: Swachchhanda Shrawan Poudel (Nextron Systems). Source status: experimental; severity: high. Source dates: 2025-11-25 / not supplied.

{
  "category": "process_creation",
  "product": "linux"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 298071e0850c0c731142301e90d574391521789a15a887dc64233e53e57dfb98

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Script Interpreter Spawning Credential Scanner - Linux
id: f0025a69-e1b7-4dda-a53c-db21fa2d4071
related:
    - id: 0f60b28c-64dd-4e2c-9a63-5334d3e3a6e6
      type: similar
status: experimental
description: |
    Detects a script interpreter process (like node.js or bun) spawning a known credential scanning tool (e.g., trufflehog, gitleaks).
    This behavior is indicative of an attempt to find and steal secrets, as seen in the "Shai-Hulud: The Second Coming" campaign.
references:
    - https://github.com/asyncapi/cli/blob/2efa4dff59bc3d3cecdf897ccf178f99b115d63d/bun_environment.js
    - https://www.stepsecurity.io/blog/sha1-hulud-the-second-coming-zapier-ens-domains-and-other-prominent-npm-packages-compromised
    - https://www.endorlabs.com/learn/shai-hulud-2-malware-campaign-targets-github-and-cloud-credentials-using-bun-runtime
    - https://semgrep.dev/blog/2025/digging-for-secrets-sha1-hulud-the-second-coming-of-the-npm-worm/
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-11-25
tags:
    - attack.credential-access
    - attack.t1552
    - attack.execution
    - attack.collection
    - attack.t1005
    - attack.t1059.004
logsource:
    category: process_creation
    product: linux
detection:
    selection_parent:
        ParentImage|endswith:
         # Add more script interpreters as needed
            - '/node'
            - '/bun'
    selection_child:
        - Image|endswith:
              - '/trufflehog'
              - '/gitleaks'
        - CommandLine|contains:
              - 'trufflehog'
              - 'gitleaks'
    condition: all of selection_*
falsepositives:
    - Legitimate pre-commit hooks or CI/CD pipeline jobs that use a script to run a credential scanner as part of a security check.
level: high

Original YAML and metadata in JSON

False positives

• Legitimate pre-commit hooks or CI/CD pipeline jobs that use a script to run a credential scanner as part of a security check.

Source references

• https://github.com/asyncapi/cli/blob/2efa4dff59bc3d3cecdf897ccf178f99b115d63d/bun_environment.js
• https://www.stepsecurity.io/blog/sha1-hulud-the-second-coming-zapier-ens-domains-and-other-prominent-npm-packages-compromised
• https://www.endorlabs.com/learn/shai-hulud-2-malware-campaign-targets-github-and-cloud-credentials-using-bun-runtime
• https://semgrep.dev/blog/2025/digging-for-secrets-sha1-hulud-the-second-coming-of-the-npm-worm/