# CVE-2015-8371: composer: Composer before 2016-02-10 allows cache poisoning from other projects built on the same host

CVE-2015-8371 is fixed in composer on 1 platform, first by DEBIAN-CVE-2015-8371, released September 21, 2023. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2015-8371
- Priority: High
- CVSS: 8.8 (high)
- EPSS: 0.0072
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 21, 2023

## Description

Composer before 2016-02-10 allows cache poisoning from other projects built on the same host. This results in attacker-controlled code entering a server-side build process. The issue occurs because of the way that dist packages are cached. The cache key is derived from the package name, the dist type, and certain other data from the package repository (which may simply be a commit hash, and thus can be found by an attacker). Versions through 1.0.0-alpha11 are affected, and 1.0.0 is unaffected.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | composer Debian 12.15 (bookworm) | 1.0.0~alpha11-3 | [DEBIAN-CVE-2015-8371](https://patchblox.com/security/data/fix/linux/debian-cve-2015-8371.md) | Sep 21, 2023 |
| Linux | composer Debian 13.5 (trixie) | 1.0.0~alpha11-3 | [DEBIAN-CVE-2015-8371](https://patchblox.com/security/data/fix/linux/debian-cve-2015-8371.md) | Sep 21, 2023 |
| Linux | composer Debian 14 | 1.0.0~alpha11-3 | [DEBIAN-CVE-2015-8371](https://patchblox.com/security/data/fix/linux/debian-cve-2015-8371.md) | Sep 21, 2023 |

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