High 7.7Published Sep 1, 2026

CVE-2026-84361Composer: Perforce source URL permits P4PORT `rsh:` command execution

Updated under an hour ago (2026-10-19 07:23 UTC)

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Exploited in the last 30 days

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.

CVSS: 7.7 HIGH (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Weakness (CWE): CWE-78
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Sep 3, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

composer composer composer:composer (from the name)	from 1.0, < 2.2.30; from 2.3.0, < 2.10.3	CNA record

References

https://github.com/composer/composer/security/advisories/GHSA-rvx4-ffvw-m9q3x-refsource-confirm
https://github.com/composer/composer/commit/0aac50528e83ed635cf788333635897469440220x-refsource-misc
https://github.com/composer/composer/commit/199ad81a9cc6a2a5164ad79a8da26b2e19e521afx-refsource-misc
https://github.com/composer/composer/releases/tag/2.10.3x-refsource-misc
https://github.com/composer/composer/releases/tag/2.2.30x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.