Composer is a dependency manager for PHP. On the 2.x branch prior to versions 2.2.24 and 2.7.7, the `composer install` command running inside a git/hg repository which has specially crafted branch names can lead to command injection. This requires cloning untrusted repositories. Patches are available in version 2.2.24 for 2.2 LTS or 2.7.7 for mainline. As a workaround, avoid cloning potentially compromised repositories.
https://github.com/composer/composer/security/advisories/GHSA-v9qv-c7wm-wgmf
https://github.com/composer/composer/commit/fc57b93603d7d90b71ca8ec77b1c8a9171fdb467
https://github.com/composer/composer/commit/6bd43dff859c597c09bd03a7e7d6443822d0a396