USN-1251-1: Firefox and Xulrunner vulnerabilities

Ubuntu Security Notice USN-1251-1

10th November, 2011

firefox, xulrunner-1.9.2 vulnerabilities

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

  • Ubuntu 10.10
  • Ubuntu 10.04 LTS


Multiple vulnerabilities have been fixed in Firefox and Xulrunner.

Software description

  • firefox - Mozilla Open Source web browser
  • xulrunner-1.9.2 - Mozilla Gecko runtime environment


It was discovered that CVE-2011-3004, which addressed possible privilege
escalation in addons, also affected Firefox 3.6. An attacker could
potentially exploit Firefox when an add-on was installed that used
loadSubscript in vulnerable ways. (CVE-2011-3647)

Yosuke Hasegawa discovered that the Mozilla browser engine mishandled
invalid sequences in the Shift-JIS encoding. A malicious website could
possibly use this flaw this to steal data or inject malicious scripts into
web content. (CVE-2011-3648)

Marc Schoenefeld discovered that using Firebug to profile a JavaScript file
with many functions would cause Firefox to crash. An attacker might be able
to exploit this without using the debugging APIs which would potentially
allow an attacker to remotely crash the browser. (CVE-2011-3650)

Update instructions

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

Ubuntu 10.10:
firefox 3.6.24+build2+nobinonly-0ubuntu0.10.10.1
Ubuntu 10.04 LTS:
firefox 3.6.24+build2+nobinonly-0ubuntu0.10.04.1

To update your system, please follow these instructions:

After a standard system upgrade you need to restart Firefox and any
applications that use Xulrunner to effect the necessary changes.


CVE-2011-3647, CVE-2011-3648, CVE-2011-3650