USN-779-1: Firefox and Xulrunner vulnerabilities

Ubuntu Security Notice USN-779-1

12th June, 2009

firefox-3.0, xulrunner-1.9 vulnerabilities

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


Several flaws were discovered in the browser and JavaScript engines of
Firefox. If a user were tricked into viewing a malicious website, a remote
attacker could cause a denial of service or possibly execute arbitrary code
with the privileges of the user invoking the program. (CVE-2009-1392,
CVE-2009-1832, CVE-2009-1833, CVE-2009-1837, CVE-2009-1838)

Pavel Cvrcek discovered that Firefox would sometimes display certain
invalid Unicode characters as whitespace. An attacker could exploit this to
spoof the location bar, such as in a phishing attack. (CVE-2009-1834)

Gregory Fleischer, Adam Barth and Collin Jackson discovered that Firefox
would allow access to local files from resources loaded via the file:
protocol. If a user were tricked into downloading then opening a malicious
file, an attacker could steal potentially sensitive information.
(CVE-2009-1835, CVE-2009-1839)

Shuo Chen, Ziqing Mao, Yi-Min Wang, and Ming Zhang discovered that Firefox
did not properly handle error responses when connecting to a proxy server.
If a remote attacker were able to perform a man-in-the-middle attack, this
flaw could be exploited to view sensitive information. (CVE-2009-1836)

Wladimir Palant discovered Firefox did not check content-loading policies
when loading external script files into XUL documents. As a result, Firefox
might load malicious content under certain circumstances. (CVE-2009-1840)

It was discovered that Firefox could be made to run scripts with elevated
privileges. If a user were tricked into viewing a malicious website, an
attacker could cause a chrome privileged object, such as the browser
sidebar, to run arbitrary code via interactions with the attacker
controlled website. (CVE-2009-1841)

Update instructions

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

Ubuntu 9.04:
firefox-3.0 3.0.11+build2+nobinonly-0ubuntu0.9.04.1
abrowser 3.0.11+build2+nobinonly-0ubuntu0.9.04.1
Ubuntu 8.10:
firefox-3.0 3.0.11+build2+nobinonly-0ubuntu0.8.10.1
abrowser 3.0.11+build2+nobinonly-0ubuntu0.8.10.1
Ubuntu 8.04 LTS:
firefox-3.0 3.0.11+build2+nobinonly-0ubuntu0.8.04.1

To update your system, please follow these instructions:

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


CVE-2009-1392, CVE-2009-1832, CVE-2009-1833, CVE-2009-1834, CVE-2009-1835, CVE-2009-1836, CVE-2009-1837, CVE-2009-1838, CVE-2009-1839, CVE-2009-1840, CVE-2009-1841