---
title: "CVE-2011-4327\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-2011-4327?format=md
keywords: index, follow
---

# CVE-2011-4327

Publication date 3 February 2014

Last updated 6 June 2026

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**5.5 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2011-4327?format=md#impact-score)

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## Description

ssh-keysign.c in ssh-keysign in OpenSSH before 5.8p2 on certain platforms
executes ssh-rand-helper with unintended open file descriptors, which
allows local users to obtain sensitive key information via the ptrace
system call.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2011-4327?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| openssh | 11.10 oneiric | Not affected |
| 11.04 natty | Not affected |
| 10.10 maverick | Not affected |
| 10.04 LTS lucid | Not affected |
| 8.04 LTS hardy | 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

---

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

Per OpenSSH, platforms with /dev/random are not affected.

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

5.5 · Medium

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 5.5 · Medium |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2011-4327)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2011-4327)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2011-4327)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2011-4327)

### Other references

* <http://www.openwall.com/lists/oss-security/2011/11/21/8>
* <http://www.openssh.com/txt/release-5.8p2>
* <http://www.openssh.com/txt/portable-keysign-rand-helper.adv>
* <http://www.nessus.org/plugins/index.php?view=single&id=53841>
* <https://www.cve.org/CVERecord?id=CVE-2011-4327>