---
title: "CVE-2015-5331\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-2015-5331?format=md
keywords: index, follow
---

# CVE-2015-5331

Publication date 22 February 2016

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**4.3 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2015-5331?format=md#impact-score)

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## Description

Moodle 2.9.x before 2.9.3 does not properly check the contact list before
authorizing message transmission, which allows remote authenticated users
to bypass intended access restrictions and conduct spam attacks via the
messaging API.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2015-5331?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| moodle | 15.10 wily | Not affected |
| 15.04 vivid | Not affected |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not affected |

---

* [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

---

### [seth-arnold](https://launchpad.net/~seth-arnold)

affects only 2.9.x

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

4.3 · Medium

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 4.3 · Medium |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-5331)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2015-5331)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2015-5331)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2015-5331)

### Other references

* <https://moodle.org/mod/forum/discuss.php?d=323228#p1297699>
* <https://www.cve.org/CVERecord?id=CVE-2015-5331>