The remote host is missing an update to xulrunner-1.9 announced via advisory USN-779-1.

The problem can be corrected by upgrading your system to the following package versions: Ubuntu 8.04 LTS: firefox-3.0 3.0.11+build2+nobinonly-0ubuntu0.8.04.1 xulrunner-1.9 1.9.0.11+build2+nobinonly-0ubuntu0.8.04.1 Ubuntu 8.10: abrowser 3.0.11+build2+nobinonly-0ubuntu0.8.10.1 firefox-3.0 3.0.11+build2+nobinonly-0ubuntu0.8.10.1 xulrunner-1.9 1.9.0.11+build2+nobinonly-0ubuntu0.8.10.2 Ubuntu 9.04: abrowser 3.0.11+build2+nobinonly-0ubuntu0.9.04.1 firefox-3.0 3.0.11+build2+nobinonly-0ubuntu0.9.04.1 xulrunner-1.9 1.9.0.11+build2+nobinonly-0ubuntu0.9.04.1 After a standard system upgrade you need to restart Firefox and any applications that use xulrunner, such as Epiphany, to effect the necessary changes. https://secure1.securityspace.com/smysecure/catid.html?in=USN-779-1

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)