USN-255-1: openssh vulnerability

22 February 2006

openssh vulnerability

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

  • Ubuntu 5.10
  • Ubuntu 5.04
  • Ubuntu 4.10

Software Description


Tomas Mraz discovered a shell code injection flaw in scp. When doing local-to-local or remote-to-remote copying, scp expanded shell escape characters. By tricking an user into using scp on a specially crafted file name (which could also be caught by using an innocuous wild card like ‘*‘), an attacker could exploit this to execute arbitrary shell commands with the privilege of that user.

Please be aware that scp is not designed to operate securely on untrusted file names, since it needs to stay compatible with rcp. Please use sftp for automated systems and potentially untrusted file names.

Update instructions

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

Ubuntu 5.10
Ubuntu 5.04
Ubuntu 4.10

To update your system, please follow these instructions: