USN-1288-1: vsftpd vulnerability

7 December 2011

vsftpd vulnerability

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 11.10
  • Ubuntu 11.04
  • Ubuntu 10.10
  • Ubuntu 10.04 LTS

Summary

Vsftpd or other applications could be made to crash if vsftpd received specially crafted network traffic.

Software Description

  • vsftpd - FTP server written for security

Details

It was discovered that the 2.6.35 and earlier Linux kernel does not properly handle a high rate of creation and cleanup of network namespaces, which makes it easier for remote attackers to cause a denial of service (memory consumption) in applications that require a separate namespace per connection, like vsftpd. This update adjusts vsftpd to only use network namespaces on kernels that are known to be not affected.

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 11.10
vsftpd - 2.3.2-3ubuntu5.1
Ubuntu 11.04
vsftpd - 2.3.2-3ubuntu4.1
Ubuntu 10.10
vsftpd - 2.3.0~pre2-4ubuntu2.3
Ubuntu 10.04 LTS
vsftpd - 2.2.2-3ubuntu6.3

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

In general, a standard system update will make all the necessary changes.

References