# CVE-2023-43655: composer: Composer is a dependency manager for PHP

CVE-2023-43655 is fixed in composer on 1 platform, first by DEBIAN-CVE-2023-43655, released September 29, 2023. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2023-43655
- Priority: High
- CVSS: 8.8 (high)
- EPSS: 0.0153
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 29, 2023

## Description

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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | composer Debian 12.15 (bookworm) | 2.5.5-1+deb12u4 | [DEBIAN-CVE-2023-43655](https://patchblox.com/security/data/fix/linux/debian-cve-2023-43655.md) | Sep 29, 2023 |
| Linux | composer Debian 13.5 (trixie) | 2.6.4-1 | [DEBIAN-CVE-2023-43655](https://patchblox.com/security/data/fix/linux/debian-cve-2023-43655.md) | Sep 29, 2023 |
| Linux | composer Debian 14 | 2.6.4-1 | [DEBIAN-CVE-2023-43655](https://patchblox.com/security/data/fix/linux/debian-cve-2023-43655.md) | Sep 29, 2023 |
| Linux | composer Ubuntu 18.04.6 LTS (bionic) | 1.6.3-1ubuntu0.1~esm2 | [composer 1.6.3-1ubuntu0.1~esm2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-composer-1.6.3-1ubuntu0.1-esm2.md) | Jun 10, 2024 |
| Linux | composer Ubuntu 20.04 LTS (focal) | 1.10.1-1ubuntu0.1~esm2 | [composer 1.10.1-1ubuntu0.1~esm2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-composer-1.10.1-1ubuntu0.1-esm2.md) | Jun 10, 2024 |
| Linux | composer Ubuntu 22.04.1 LTS (jammy) | 2.2.6-2ubuntu4+esm1 | [composer 2.2.6-2ubuntu4+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-composer-2.2.6-2ubuntu4-esm1.md) | Jun 10, 2024 |
| Linux | composer amzn 2023 | 2.5.8-2.amzn2023.0.1 | [ALAS2023-2023-384](https://patchblox.com/security/data/fix/linux/alas2023-2023-384.md) | Oct 12, 2023 |

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Data as of 2026-11-08T13:06:02Z 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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