Please do not open a public issue for a security problem. Use GitHub's private vulnerability reporting on this repository:

1. Go to https://github.com/A-G0D/changegate/security/advisories/new.
2. Describe the issue, the affected version/commit, and a minimal reproduction.

If private reporting is unavailable to you, open a normal issue that says only "security report — please contact me for details" without exploit details.

changegate is a reader: by default it parses a diff and inspects added lines. It does not stage, commit, or modify files, and it makes no network calls. The two places where it interacts with the environment are:

1. --test-cmd / --lint-cmd execute a command you provide, as your user, inside the repository under test, with *_API_KEY, *_TOKEN, *SECRET*, *PASSWORD* environment variables removed and a timeout. Only run commands on repositories whose code you trust. This is opt-in; a plain changegate check never executes repository code.
2. Reading files and running git diff in the target repository. Paths are passed to git directly (no shell), never interpolated into a shell string.

• A credential that the documentation claims to detect but that passes the gate when it is a realistic credential pattern (regex gaps, catastrophic backtracking, rule bypass with near-identical syntax). Please include a minimal, clearly synthetic reproduction.
• A way to make the gate print a full credential or personal data instead of a redacted excerpt.
• Command or path injection through configuration values, CLI arguments, or a crafted patch file.
• A crash or infinite loop triggered by a malformed diff (denial of service for CI).
• A repo-controlled file that makes the gate silently skip content it should scan.

• The gate not detecting a credential pattern that is intentionally not in its rule set. The rules are documented and intentionally small; open a feature request instead.
• A hostile repository whose tests you deliberately ran with --test-cmd.
• Findings that are technically true but not exploitable (for example, a warning about eval in a hand-written parser) — treat those as rule-quality issues.
• Vulnerabilities in tools this project is often used alongside (gitleaks, CodeQL, GitHub Actions).

The repository itself is protected by the same CI it ships: lint, tests, a deterministic demo, a gitleaks secret scan, and CodeQL. Dependabot security updates and private vulnerability reporting are enabled for the repository.