---
title: "CVE-2006-20001\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-2006-20001?format=md
keywords: index, follow
---

# CVE-2006-20001

Publication date 17 January 2023

Last updated 4 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**7.5 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2006-20001?format=md#impact-score)

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## Description

A carefully crafted If: request header can cause a memory read, or write of
a single zero byte, in a pool (heap) memory location beyond the header
value sent. This could cause the process to crash.
This issue affects Apache HTTP Server 2.4.54 and earlier.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| apache2 | 26.04 LTS resolute | Fixed 2.4.55-1ubuntu1 |
| 25.10 questing | Fixed 2.4.55-1ubuntu1 |
| 25.04 plucky | Fixed 2.4.55-1ubuntu1 |
| 24.10 oracular | Fixed 2.4.55-1ubuntu1 |
| 24.04 LTS noble | Fixed 2.4.55-1ubuntu1 |
| 23.10 mantic | Fixed 2.4.55-1ubuntu1 |
| 23.04 lunar | Fixed 2.4.55-1ubuntu1 |
| 22.10 kinetic | Fixed 2.4.54-2ubuntu1.1 |
| 22.04 LTS jammy | Fixed 2.4.52-1ubuntu4.3 |
| 20.04 LTS focal | Fixed 2.4.41-4ubuntu3.13 |
| 18.04 LTS bionic | Fixed 2.4.29-1ubuntu4.26 |
| 16.04 LTS xenial | Fixed 2.4.18-2ubuntu3.17+esm8  Ubuntu Pro |
| 14.04 LTS trusty | Vulnerable |

---

* [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-2006-20001?format=md#patch-details)

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### 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 |
| --- | --- |
| apache2 | * Upstream:   [7469547](https://github.com/apache/httpd/commit/7469547c3f617717ca545d0f7c56d01134703813) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.5 · High

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.5 · High |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-20001)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2006-20001)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2006-20001)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2006-20001)

### Related Ubuntu Security Notices (USN)

+ [USN-5834-1](https://usn.ubuntu.com/USN-5834-1)
+ Apache HTTP Server vulnerabilities
+ 31 January 2023

+ [USN-5839-1](https://usn.ubuntu.com/USN-5839-1)
+ Apache HTTP Server vulnerabilities
+ 1 February 2023

### Other references

* <https://www.openwall.com/lists/oss-security/2023/01/17/5>
* <https://httpd.apache.org/security/vulnerabilities_24.html#CVE-2006-20001>
* <https://httpd.apache.org/security/vulnerabilities_24.html>
* <https://www.cve.org/CVERecord?id=CVE-2006-20001>