VNX-SEC-051: RubyGems API token

Reports a RubyGems.org API key (rubygems_ + exactly 48 hex characters) in any file; bare prefixes, longer identifiers, placeholders and CI secret references are not reported.

Field	Value
Rule ID	`VNX-SEC-051`
Severity	Critical
SARIF level	`error`
Kind	`secrets`
Languages	Any file
CWE	CWE-798
CAPEC	CAPEC-191
ATT&CK	T1195.002
CWSS vector	`CWSS:1.0/TI:C/AP:A/AL:A/IC:N/FC:LT/RP:N/RL:A/AV:I/AS:N/IN:A/SC:A/BI:C/DI:H/EX:H/EC:N/P:W`
Tags	`secrets` `rubygems` `supply-chain` `credentials`
Source	`internal/sast/rules/vnx-sec-051.rego`

Overview

This rule reports a RubyGems.org API key, rubygems_ followed by exactly 48 lower-case hex characters as a whole token, wherever it appears: ~/.gem/credentials, GEM_HOST_API_KEY in a workflow, a Rakefile or a shell script. Not reported: the bare prefix, shorter or longer hex runs, placeholder bodies, ${{ secrets.X }} references, and test, fixture or vendored paths.

What Gets Flagged

:rubygems_api_key: rubygems_<48 hex characters>

env:
  GEM_HOST_API_KEY: "rubygems_<48 hex characters>"

Why This Matters

Hardcoded rubygems api token values are routinely scraped by automated bots within minutes of a public push, and then used to access the account, exfiltrate data, or pivot into downstream services. Once the credential is in git history it is permanently in third-party hands.

Remediation

Revoke the leaked credential in the provider’s console immediately.
Replace with a short-lived alternative, OAuth 2.0 access tokens, IAM role assumption, OIDC federation, wherever the platform supports it.
Store the new credential in a secrets manager (AWS Secrets Manager, HashiCorp Vault, GitHub Actions secrets, Doppler).
Audit the provider’s access logs for activity you did not initiate between the leak and the revocation.
Purge from git history with git filter-repo or BFG, then re-scan with gitleaks/truffleHog to confirm no other secrets remain.
Enable push protection so future commits are blocked at the developer machine.

References

CWE-798: Use of Hard-coded Credentials
gitleaks rubygems-api-token
truffleHog
OWASP Credentials Management Cheat Sheet
MITRE ATT&CK T1552.001 – Credentials In Files
git-filter-repo

Suppressing this rule

Put a nosec comment on the line, or on line 1 to cover the whole file. Use the comment marker of the file’s language (#, //, -- or ;):

# nosec vnx-sec-051
// nosec vnx-sec-051

Or record an ignore rule: vulnetix ignore add --rule vnx-sec-051 --reason "...". See Suppressing findings.