Multiple security issues have been found in Iceweasel, Debian's version of the Mozilla Firefox web browser. The Common Vulnerabilities and Exposures project identifies the following problems:
Jean-Max Reymond and Ucha Gobejishvili discovered a use-after-free vulnerability which occurs when resizing of a canvas element is triggered in concert with style changes. A web page containing malicious content can cause Iceweasel to crash, or potentially, execute arbitrary code with the privileges of the user running Iceweasel.
Bas Venis reported a flaw in the handling of add-ons installation. A remote attacker can take advantage of this flaw to bypass the add-on installation prompt and trick a user into installing an add-on from a malicious source.
For the oldstable distribution (wheezy), these problems have been fixed in version 38.2.1esr-1~deb7u1.
For the stable distribution (jessie), these problems have been fixed in version 38.2.1esr-1~deb8u1.
For the unstable distribution (sid), these problems have been fixed in version 38.2.1esr-1.
We recommend that you upgrade your iceweasel packages.