USN-811-1: Firefox and Xulrunner vulnerability

8 August 2009

firefox-3.0, xulrunner-1.9 vulnerability

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

  • Ubuntu 9.04
  • Ubuntu 8.10
  • Ubuntu 8.04 LTS

Software Description

  • firefox-3.0
  • xulrunner-1.9


Juan Pablo Lopez Yacubian discovered that Firefox did not properly display invalid URLs. If a user were tricked into accessing a malicious website, an attacker could exploit this to spoof the location bar, such as in a phishing attack. Furthermore, if the malicious website had a valid SSL certificate, Firefox would display the spoofed page as trusted.

Update instructions

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

Ubuntu 9.04
abrowser - 3.0.13+nobinonly-0ubuntu0.9.04.1
firefox-3.0 - 3.0.13+nobinonly-0ubuntu0.9.04.1
xulrunner-1.9 -
Ubuntu 8.10
abrowser - 3.0.13+nobinonly-0ubuntu0.8.10.1
firefox-3.0 - 3.0.13+nobinonly-0ubuntu0.8.10.1
xulrunner-1.9 -
Ubuntu 8.04 LTS
firefox-3.0 - 3.0.13+nobinonly-0ubuntu0.8.04.1
xulrunner-1.9 -

To update your system, please follow these instructions:

After a standard system upgrade you need to restart Firefox and any applications that use xulrunner, such as Epiphany, to effect the necessary changes.