Almost all supported Ubuntu operating systems were affected by this problem
On March 29, Canonical published in a security notice details about a Bind vulnerability for its Ubuntu 12.10, Ubuntu 12.04 LTS, Ubuntu 11.10, and Ubuntu 10.04 LTS operating systems.According to Canonical, Bind could be made to consume memory or crash, if it received specially crafted network traffic.
It was discovered that Bind incorrectly handled regular expression checking. A remote attacker could use this flaw to cause Bind to consume an excessive amount of memory, possibly resulting in a denial of service.
For a more detailed description of the security problems, you can visit Canonical's security notification.
Users can simply fix the security flaws by upgrading the operating systems to the latest bind specific to each distribution.
A normal system update, executed with the Update Manager, will implement all the necessary changes. A complete system restart is not necessary.