---
title: "CVE-2011-1720\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-2011-1720?format=md
keywords: index, follow
---

# CVE-2011-1720

Publication date 11 May 2011

Last updated 24 July 2024

---

Ubuntu priority

**Medium**

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

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## Description

The SMTP server in Postfix before 2.5.13, 2.6.x before 2.6.10, 2.7.x before
2.7.4, and 2.8.x before 2.8.3, when certain Cyrus SASL authentication
methods are enabled, does not create a new server handle after client
authentication fails, which allows remote attackers to cause a denial of
service (heap memory corruption and daemon crash) or possibly execute
arbitrary code via an invalid AUTH command with one method followed by an
AUTH command with a different method.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| postfix | 11.04 natty | Fixed 2.8.2-1ubuntu2.1 |
| 10.10 maverick | Fixed 2.7.1-1ubuntu0.2 |
| 10.04 LTS lucid | Fixed 2.7.0-1ubuntu0.2 |
| 8.04 LTS hardy | Fixed 2.5.1-2ubuntu1.4 |
| 6.06 LTS dapper | Fixed 2.2.10-1ubuntu0.4 |

---

* [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-2011-1720)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2011-1720)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2011-1720)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2011-1720)

### Related Ubuntu Security Notices (USN)

+ [USN-1131-1](https://usn.ubuntu.com/USN-1131-1)
+ Postfix vulnerability
+ 11 May 2011

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2011-1720>