PHP CodeSniffer versions before v3.13.6 and v4.0.2 contain a command injection vulnerability in the code creating the Gitblame, Hgblame and Svnblame report(s).

As a result, running PHP CodeSniffer over untrusted files, for example, in a CI pipeline that scans pull requests, or on a developer machine reviewing third-party code, could result in attacker-controlled shell commands being executed when the Gitblame, Hgblame or Svnblame report(s) would process a file whose name contains shell metacharacters.

The issue has been fixed in PHP CodeSniffer v3.13.6 and v4.0.2. We recommend all users upgrade to these versions at their earliest convenience.

Users of PHP CodeSniffer who cannot upgrade immediately should ensure they do not use the Gitblame, Hgblame or the Svnblame reports when scanning untrusted code.

This is especially relevant for CI jobs, pre-commit or review tooling, automated review services, and any service that scans untrusted repositories or uploaded source trees.

Many thanks to both @Faze-up and @edorian for responsibly disclosing this vulnerability.

Please report security vulnerabilities privately via [the "Security and quality" tab on the PHP CodeSniffer repository](https://github.com/PHPCSStandards/PHP CodeSniffer/security).