The Ubuntu 15.04, 14.04 LTS, and Ubuntu 12.04 LTS operating systems have been updated in order to fix an important Django vulnerability that has recently been identified.
This is not the first Django vulnerability that has been found in this release cycle, but it's not a major issue. According to the report, Django could have been made to crash if it received specially crafted network traffic.
"Lin Hua Cheng discovered that Django incorrectly handled the session store. A remote attacker could use this issue to cause the session store to fill up, resulting in a denial of service," the report says.
This is the problem that has been identified and fixed in Ubuntu OSes. For a more detailed description of the issue, you can see Canonical's security notification. Users have been advised to upgrade their systems as soon as possible.
In general, a standard system update will make all the necessary changes and you don't have to restart the PC in order to complete the update.
You can also use the terminal to update the system. Just enter these commands in a terminal near you:
sudo apt-get dist-upgrade