Composer: Tampered vendor/composer Files Run Code When Composer Runs

Published as "Composer code execution and possible privilege escalation via compromised InstalledVersions.php or installed.php"

high Composer · Last reviewed Nov 10, 2026

CVE: CVE-2024-24821
GHSA: GHSA-7c6p-848j-wh5h
Packagist: PKSA-jn72-4kr8-gj3h
Reported: Feb 8, 2024

Lets code planted in a project's vendor/composer files run as whoever runs Composer there, including root when Composer runs with sudo.

Affected and fixed versions

In composer/composer. Find the row for the version you run, and update to the release next to it.

If you run	Update to	Support
2.3.0-rc1 – 2.6.x	2.7.0	Supported

Show 1 older branch, no longer supported

2.0.0-alpha1 – 2.2.22

2.2.23

Upgrade

Run the line for the branch you are on.

composer require composer/composer:^2.7.0

What this means

Composer loaded PHP files from the project's own vendor/composer directory each time it ran. If someone could change those files, their code ran as whoever ran Composer next. With sudo, that means root.

The files are vendor/composer/InstalledVersions.php and vendor/composer/installed.php. Every Composer command was affected, including composer self-update. See the Composer advisory and the fixes for 2.7 and 2.2 LTS.

Who is affected

Anyone running composer/composer where someone else could have changed those files. The Composer team calls these setups high risk:

Running Composer with sudo.
CI pipelines that may run Composer on untrusted projects.
Shared environments where several developers run Composer on the same project.

What to do

Update Composer to 2.7.0, or to 2.2.23 if you're on the 2.2 LTS line. If you can't update yet, the Composer team advises:

Remove the right to run Composer with sudo for all users.
Don't run Composer in a directory you don't trust, or first check those two files for code you didn't expect.
Reset the two files by deleting them and running composer install --no-scripts --no-plugins.

Reported by edonsec.

Check your app with an agent

Paste this into a coding agent that can read your project, such as Claude Code, Codex or Amp. It checks your composer.lock against the versions above and tells you what to update, without changing anything.

Check whether the PHP project you have access to is affected by this security advisory, and tell me what to update. Do a read-only check: don't edit files, don't run composer update or composer require, and don't try to reproduce the flaw.

Advisory: Composer: Tampered vendor/composer Files Run Code When Composer Runs (CVE-2024-24821, GHSA-7c6p-848j-wh5h)
Details: https://phpnews.net/security/composer/ghsa-7c6p-848j-wh5h

Affected versions, as Composer constraints:
- composer/composer: >=2.3.0-rc1,<2.7.0|>=2.0.0-alpha1,<2.2.23

Fixed releases on branches that still get security fixes:
- 2.3.0-rc1 – 2.6.x: update to 2.7.0

1. Find every composer.lock in the project outside vendor/ (a monorepo can have one per app) and read the installed version of each package above. Packages installed as dependencies of other packages count too.
2. Compare each installed version with its constraint: "|" separates alternative ranges, and "," means both bounds apply.
3. For each affected install, read "What this means" at https://phpnews.net/security/composer/ghsa-7c6p-848j-wh5h and check whether the project meets the conditions it describes (a feature in use, a config value, a driver). Say which conditions you could check and which you couldn't.
4. Report a table: lock file | package | installed version | affected (yes, no or unknown) | conditions met (yes, no or unknown) | update to | evidence. For each affected package, give the command that would fix it, without running it: composer update <package> --with-dependencies when it is only installed as a dependency of another package, or composer require with the fixed version when composer.json requires it directly. If the installed version is on a branch with no fixed release listed, say it needs a move to a newer branch.

Sources

← All Composer advisories