---
title: "CVE-2014-6271\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-2014-6271?format=md
keywords: index, follow
---

# CVE-2014-6271

Publication date 24 September 2014

Last updated 25 August 2025

---

Ubuntu priority

**High**

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

## Cvss 3 Severity Score

**9.8 · Critical**

[Score breakdown](https://ubuntu.com/security/CVE-2014-6271?format=md#impact-score)

Toggle side navigation

## Description

GNU Bash through 4.3 processes trailing strings after function definitions
in the values of environment variables, which allows remote attackers to
execute arbitrary code via a crafted environment, as demonstrated by
vectors involving the ForceCommand feature in OpenSSH sshd, the mod\_cgi and
mod\_cgid modules in the Apache HTTP Server, scripts executed by unspecified
DHCP clients, and other situations in which setting the environment occurs
across a privilege boundary from Bash execution, aka "ShellShock." NOTE:
the original fix for this issue was incorrect; CVE-2014-7169 has been
assigned to cover the vulnerability that is still present after the
incorrect fix.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2014-6271?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| bash | 14.04 LTS trusty | Fixed 4.3-7ubuntu1.1 |
| 12.04 LTS precise | Fixed 4.2-2ubuntu2.2 |
| 10.04 LTS lucid | Fixed 4.1-2ubuntu3.1 |

---

* [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

---

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

After updates were released for this issue, it was discovered
that the fix was incomplete. The new issue is being tracked
as CVE-2014-7169.

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

9.8 · Critical

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 9.8 · Critical |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-6271)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2014-6271)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2014-6271)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2014-6271)

### Related Ubuntu Security Notices (USN)

+ [USN-2362-1](https://usn.ubuntu.com/USN-2362-1)
+ Bash vulnerability
+ 24 September 2014

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2014-6271>
* <https://www.cisa.gov/known-exploited-vulnerabilities-catalog>