---
title: "CVE-2015-8371\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2015-8371?format=md
keywords: index, follow
---

# CVE-2015-8371

Publication date 21 September 2023

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**8.8 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2015-8371?format=md#impact-score)

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## 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.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2015-8371?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| composer | 18.04 LTS bionic | Not affected |
| 17.10 artful | Ignored end of life |
| 17.04 zesty | Ignored end of life |
| 16.10 yakkety | Ignored end of life |
| 16.04 LTS xenial | Not affected |
| 15.10 wily | Ignored end of life |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

## Notes

---

### [tyhicks](https://launchpad.net/~tyhicks)

Fixed in 10.02.2016 upstream

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

8.8 · High

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | Low |
  | Privileges required | None |
  | User interaction | Required |
  | Scope | Unchanged |
  | Confidentiality impact | High |
  | Integrity impact | High |
  | Availability impact | High |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 8.8 · High |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-8371)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2015-8371)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2015-8371)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2015-8371)

### Other references

* <http://flyingmana.de/blog_en/2016/02/14/composer_cache_injection_vulnerability_cve_2015_8371.html>
* <https://www.cve.org/CVERecord?id=CVE-2015-8371>