---
title: "CVE-2011-3656\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-2011-3656?format=md
keywords: index, follow
---

# CVE-2011-3656

Publication date 2 June 2021

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**6.1 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2011-3656?format=md#impact-score)

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## Description

Cross-site scripting (XSS) vulnerability in Mozilla Firefox before 3.6.24
and 4.x through 7 allows remote attackers to inject arbitrary web script or
HTML via vectors involving HTTP 0.9 errors, non-default ports, and
content-sniffing.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| firefox | 15.04 vivid | Not affected |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not affected |
| thunderbird | 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)
* [Patch details](https://ubuntu.com/security/CVE-2011-3656?format=md#patch-details)

### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| firefox | * Upstream:   <http://hg.mozilla.org/mozilla-central/rev/46e2febf2841> |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

6.1 · Medium

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 6.1 · Medium |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2011-3656)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2011-3656)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2011-3656)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2011-3656)

### Other references

* <https://bugzilla.mozilla.org/show_bug.cgi?id=667907>
* <https://www.cve.org/CVERecord?id=CVE-2011-3656>