Firefox could be made to crash or run programs as your login if it opened a malicious website.
A use-after-free was discovered when resizing a canvas element during restyling in some circumstances. If a user were tricked in to opening a specially crafted website, an attacker could potentially exploit this to cause a denial of service via application crash, or execute arbitrary code with the privileges of the user invoking Firefox. (CVE-2015-4497)
27 August 2015
A security issue affects these releases of Ubuntu and its derivatives:
Firefox could be made to crash or run programs as your login if it opened a malicious website.
A use-after-free was discovered when resizing a canvas element during restyling in some circumstances. If a user were tricked in to opening a specially crafted website, an attacker could potentially exploit this to cause a denial of service via application crash, or execute arbitrary code with the privileges of the user invoking Firefox. (CVE-2015-4497)
Bas Venis discovered that the addon install permission prompt could be bypassed using data: URLs in some circumstances. It was also discovered that the installation notification could be made to appear over another site. If a user were tricked in to opening a specially crafted website, an attacker could potentially exploit this to install a malicious addon. (CVE-2015-4498)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to restart Firefox to make all the necessary changes.
Vulmon