14 DAY TRIAL // Canonical published details about the libgadu vulnerability in its Ubuntu 13.10, Ubuntu 12.10, and Ubuntu 12.04 LTS operating systems.
According to the company, libgadu could have been made to crash or run programs if it received specially crafted network traffic.
It has been discovered that libgadu incorrectly handled certain Gadu-Gadu HTTP messages. A malicious remote server or a man in the middle could use this issue to cause applications using libgadu to crash, resulting in a denial of service, or possibly execute arbitrary code.
For a more detailed description of the problems, you can see Canonical's security notification.
The flaws can be fixed if you upgrade your system(s) to the latest libgadu3 package specific to each distribution. To apply the patch, run the Update Manager application.
In general, a standard system update will make all the necessary changes. A restart will be necessary in order to finish this update.