14 DAY TRIAL // Mozilla released Firefox 35, addressing nine security bugs, three of them being marked as critical by the developer as they presented the risk of compromising the machine if enough effort would be put into exploiting them.
The availability of the web browser was officially announced on Tuesday. Among the improvements there is implementation of the HTTP Public Key Pinning Extension, which enhances authentication of encrypted connections.
Significant problems have been addressed
As far as security fixes are concerned, the developer solved a Gecko Media Plugin (GMP) sandbox escape on Windows operating system. GMP sandboxing is used for hosting H.264 media files.
The bug could be used in combination with other vulnerabilities to bypass the isolated environment and compromise the GMP process. Linux and OS X platforms are not affected.
Another critical issue addressed in this release is a read-after-free vulnerability in the WebRTC component, which offers Real-Time Communication (RTC) capabilities through APIs.
Discovered by security researcher Mitchell Harper, the flaw exists because of the way tracks are handled and results in a crash that may be exploitable or in WebRTC behaving incorrectly.
In Firefox 35, Mozilla also eliminated a set of eight bugs that would lead to memory corruption under certain conditions. It is believed that if an attacker finds a way to exploit the errors, he will be able to execute arbitrary code in browser-like contexts.
“High” and “moderate” issues fixed in Firefox 35
Four moderate vulnerabilities have been addressed in the latest revision of the browser, reducing the possibilities to bypass XrayWrapper through DOM objects, read uninitialized memory in Web Audio, and the risk of cookie injection through Proxy Authenticate responses. Also repaired is the unavailability of an Origin header in sendBeacon requests.
It is worth noting that vulnerabilities marked with a “moderate” impact are generally deemed less severe because they work on custom browser configurations.
The only glitch labeled with a “high” impact patched in Firefox 35 has been reported by Google security researcher Michal Zalewski and refers to uninitialized memory use during bitmap rendering.