# CVE-2026-84361: composer: Composer is a dependency Manager for the PHP language

CVE-2026-84361 is fixed in 2 products on 1 platform, first by DEBIAN-CVE-2026-84361, released September 3, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-84361
- Priority: High
- CVSS: n/a (important)
- EPSS: 0.0050
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 1, 2026

## Description

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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | composer Debian 14 | 2.10.3-1 | [DEBIAN-CVE-2026-84361](https://patchblox.com/security/data/fix/linux/debian-cve-2026-84361.md) | Sep 3, 2026 |
| Linux | composer amzn 2023 | 2.10.3-1.amzn2023.0.1 | [ALAS2023-2026-3136](https://patchblox.com/security/data/fix/linux/alas2023-2026-3136.md) | Sep 28, 2026 |
| Linux | php-composer2 opensuse-leap 16.0 | 2.8.9-160000.5.1 | [OPENSUSE-SU-2026:21778-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21778-1.md) | Sep 6, 2026 |
| Linux | php-composer2 sles 15.6 | 2.6.4-150600.3.18.1 | [SUSE-SU-2026:4059-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4059-1.md) | Sep 8, 2026 |
| Linux | php-composer2 sles 15.7 | 2.6.4-150600.3.18.1 | [SUSE-SU-2026:4059-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4059-1.md) | Sep 8, 2026 |
| Linux | php-composer2 sles 16.0 | 2.8.9-160000.5.1 | [SUSE-SU-2026:23635-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-23635-1.md) | Sep 6, 2026 |

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Data as of 2026-11-08T19:12:23Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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