Canonical has just announced that a large number of Firefox vulnerabilities have been fixed and that version 39.0 of the browser has been added to Ubuntu 15.04 and all the other supported Ubuntu versions.

This latest version of Firefox debuted on July 3, but it took the Ubuntu maintainers almost a week to make it available in the official repositories. It usually takes a lot less than seven days to land in the distros, but this time it was a lot longer. In fact, it was long enough for Ubuntu users to start asking questions about it.

The latest version of Firefox brought a few interesting new features, like the ability to share Hello URLs on social networks, support for Unicode 8.0 skin tone emoji, SafeBrowsing malware detection lookups for downloads, support for CSS Scroll Snap Points, a Flash regression, better performance when dropping from IPv6 to IPv4, and a few other fixes.

It's all about vulnerabilities

Each new version of Firefox also comes with a ton of fixes for various vulnerabilities, besides all the features that have been mentioned earlier. It's a good idea to upgrade the browser as soon as possible.

"Karthikeyan Bhargavan discovered that NSS incorrectly handled state transitions for the TLS state machine. If a remote attacker were able to perform a man-in-the-middle attack, this flaw could be exploited to skip the ServerKeyExchange message and remove the forward-secrecy property," reads the security notice.

For a complete list of changes, you should check the security notice. The affected platforms are Ubuntu 15.04, Ubuntu 14.10, and Ubuntu 14.04 LTS. To get this, you can simply run the Update Manager application, but you can also use the terminal.

Open a terminal and enter the following commands (you will need to be root and you will need Internet access):