---
title: "CVE-2006-4020\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-2006-4020?format=md
keywords: index, follow
---

# CVE-2006-4020

Publication date 8 August 2006

Last updated 17 July 2025

---

Ubuntu priority

**Medium**

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

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## Description

scanf.c in PHP 5.1.4 and earlier, and 4.4.3 and earlier, allows
context-dependent attackers to execute arbitrary code via a sscanf PHP
function call that performs argument swapping, which increments an index
past the end of an array and triggers a buffer over-read.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| php5 | 7.04 feisty | Fixed 5.2.1-0ubuntu1.4 |
| 6.10 edgy | Fixed 5.1.6-1ubuntu2.6 |
| 6.06 LTS dapper | Fixed 5.1.2-1ubuntu3.9 |

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* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-4020)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2006-4020)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2006-4020)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2006-4020)

### Related Ubuntu Security Notices (USN)

+ [USN-342-1](https://usn.ubuntu.com/USN-342-1)
+ PHP vulnerabilities
+ 7 September 2006

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2006-4020>