Composer is a dependency Manager for the PHP language. In affected versions several files within the local working directory are included during the invocation of Composer and in the context of the executing user. As such, under certain conditions arbitrary code execution may lead to local privilege escalation, provide lateral user movement or malicious code execution when Composer is invoked within a directory with tampered files. All Composer CLI commands are affected, including composer.phar's self-update. The following scenarios are of high risk: Composer being run with sudo, Pipelines which may execute Composer on untrusted projects, Shared environments with developers who run Composer individually on the same project. This vulnerability has been addressed in versions 2.7.0 and 2.2.23. It is advised that the patched versions are applied at the earliest convenience. Where not possible, the following should be addressed: Remove all sudo composer privileges for all users to mitigate root privilege escalation, and avoid running Composer within an untrusted directory, or if needed, verify that the contents of `vendor/composer/InstalledVersions.php` and `vendor/composer/installed.php` do not include untrusted code. A reset can also be done on these files by the following:```sh rm vendor/composer/installed.php vendor/composer/InstalledVersions.php composer install --no-scripts --no-plugins ```

Composer is a dependency manager for PHP. Users publishing a composer.phar to a public web-accessible server where the composer.phar can be executed as a php file may be subject to a remote code execution vulnerability if PHP also has `register_argc_argv` enabled in php.ini. Versions 2.6.4, 2.2.22 and 1.10.27 patch this vulnerability. Users are advised to upgrade. Users unable to upgrade should make sure `register_argc_argv` is disabled in php.ini, and avoid publishing composer.phar to the web as this is not best practice.

Composer is a dependency manager for the PHP programming language. Integrators using Composer code to call `VcsDriver::getFileContent` can have a code injection vulnerability if the user can control the `$file` or `$identifier` argument. This leads to a vulnerability on packagist.org for example where the composer.json's `readme` field can be used as a vector for injecting parameters into hg/Mercurial via the `$file` argument, or git via the `$identifier` argument if you allow arbitrary data there (Packagist does not, but maybe other integrators do). Composer itself should not be affected by the vulnerability as it does not call `getFileContent` with arbitrary data into `$file`/`$identifier`. To the best of our knowledge this was not abused, and the vulnerability has been patched on packagist.org and Private Packagist within a day of the vulnerability report.

Composer is an open source dependency manager for the PHP language. In affected versions windows users running Composer to install untrusted dependencies are subject to command injection and should upgrade their composer version. Other OSs and WSL are not affected. The issue has been resolved in composer versions 1.10.23 and 2.1.9. There are no workarounds for this issue.