CVE-2026-84361

Composer is a dependency Manager for the PHP language. From 1.0 until 2.2.30 and 2.10.3, a malicious dependency package from a custom Composer repository or an untrusted composer.lock file could set source.type to perforce and source.url to an rsh: or jsh: P4PORT value. When the Perforce p4 client was installed and Composer installed the package from source through composer install or composer update, including --prefer-source, Composer\Util\Perforce passed the address to p4 without validation, causing p4 to run a local command with the privileges of the user or CI account. Packagist.org does not permit Perforce source metadata. This issue is fixed in versions 2.2.30 and 2.10.3.

Summary

If the p4 Perforce CLI client is installed, a malicious dependency package from a package repository allowing arbitrary perforce source URLs (packagist.org is safe) could execute arbitrary commands when running composer install or composer update. Composer passed a package's Perforce source address to the p4 CLI client without validating it. The p4 CLI client accepts addresses that mean "run this local command" instead of "connect to this server". This is remote code execution with the privileges of the user or CI account running Composer.

Am I affected?

You are only affected if all of the following are true:

• The Perforce p4 command line client is installed and on the PATH of the machine running Composer.
• An attacker can control a package metadata's source section with a perforce type. Packagist.org does not allow perforce source metadata, so you are only exploitable if you rely on another Composer repository (any custom composer-type repository, or an inline package repository entry), or a composer.lock file you obtained from somewhere you do not trust.
• The package gets installed from source, either because it has no dist artifact or because source installs are selected (for example --prefer-source).

Plainly not affected: anyone without the p4 client installed, which is the large majority of Composer users. Perforce is an optional VCS integration. Also not affected: projects that only consume packages from Packagist.org, which does not allow Perforce source repositories and therefore cannot serve a package with a Perforce source address.

Most realistic way to get hit: a developer workstation or CI image that has Perforce tooling installed, pulling packages from a private or third party Composer repository that an attacker has compromised.

Patched versions

Composer now validates Perforce source addresses before handing them to the p4 client, and accepts only real network endpoints (an optional tcp/ssl transport with a host and port). Addresses that make the client spawn a local process are rejected, and the package fails validation on both update and install, before any p4 command runs. Fixed in Composer 2.10.3 and 2.2.30.

Note: If you legitimately use Perforce with an unusual P4PORT value that is not a plain host and port, Composer will now reject it.

Workarounds

Upgrading is the only complete fix.

Risk reduction short of upgrading:

• Remove the p4 client from the PATH of machines that run Composer but do not use Perforce. This fully blocks this specific attack, since the vulnerability depends on that client being present.
• Restrict configured repositories to sources you control or trust, and treat lock files from untrusted sources as untrusted input.

Composer is a dependency Manager for the PHP language. From 1.0 until 2.2.30 and 2.10.3, a malicious dependency package from a custom Composer repository or an untrusted composer.lock file could set source.type to perforce and source.url to an rsh: or jsh: P4PORT value. When the Perforce p4 client was installed and Composer installed the package from source through composer install or composer update, including --prefer-source, Composer\Util\Perforce passed the address to p4 without validation, causing p4 to run a local command with the privileges of the user or CI account. Packagist.org does not permit Perforce source metadata. This issue is fixed in versions 2.2.30 and 2.10.3.

Composer is a dependency Manager for the PHP language. From 1.0 until 2.2.30 and 2.10.3, a malicious dependency package from a custom Composer repository or an untrusted composer.lock file could set source.type to perforce and source.url to an rsh: or jsh: P4PORT value. When the Perforce p4 client was installed and Composer installed the package from source through composer install or composer update, including --prefer-source, Composer\Util\Perforce passed the address to p4 without validation, causing p4 to run a local command with the privileges of the user or CI account. Packagist.org does not permit Perforce source metadata. This issue is fixed in versions 2.2.30 and 2.10.3.

These are all security issues fixed in the php-composer2-2.10.3-2.1 package on the GA media of openSUSE Tumbleweed.

This update for php-composer2 fixes the following issue:

• CVE-2026-84361: Arbitrary code execution via malicious Perforce source URL (bsc#1278257).

This update for php-composer2 fixes the following issue:

• CVE-2026-84361: Arbitrary code execution via malicious Perforce source URL (bsc#1278257).

This update for php-composer2 fixes the following issue:

• CVE-2026-84361: Arbitrary code execution via malicious Perforce source URL (bsc#1278257).

This update for php-composer2 fixes the following issues:

• CVE-2026-45793: GitHub OAuth tokens failing regex validation can cause credential disclosure (bsc#1271504).
• CVE-2026-59944: path traversal and link following issue can make files world readable and executable (bsc#1279898).
• CVE-2026-59946: package bin entries with path segments can cause unintended host file permission modifications (bsc#1271152).
• CVE-2026-59947: unsanitized URL credential handling in debug output within Composer can allow sensitive token disclosure (bsc#1271130).
• CVE-2026-59948: missing package name validation during dependency resolution in Composer can allow path traversal (bsc#1271123).
• CVE-2026-84361: arbitrary code execution via malicious Perforce source URL (bsc#1278257).

Changes for php-composer2:

• version update to 2.2.30:

• Fixed command injection via malicious Perforce url (GHSA-rvx4-ffvw-m9q3)
• Sanitize URL-embedded usernames/token in a few more places (#13045)
• Fixed matching of gitlab URLs to avoid possible credential leak to the wrong domain (#13042)

• fix a regression on s390x due last change (bsc#1271729).

• version update to 2.2.29:

• Validate package names (GHSA-499r-g7pc-vmp9)
• Validate package bin paths against path traversal (GHSA-gjfg-22fp-rrxx)
• Sanitize URL-embedded usernames/token in verbose output (GHSA-g6xq-892h-64w3)
• Only follow HTTP redirects from HTTP responses (#12948)
• Prevent phar metadata unserialization on unsafe PHP versions (#12946)
• Sanitize JSON parse errors in http responses to avoid leaking response body data (#12959)
• Fixed GitHub token validation to be even more relaxed (#12856)

• version update to 2.2.28.