Just update the operating system in order to fix the problems
On April 4, Canonical published in a security notice details about PostgreSQL vulnerabilities for its Ubuntu 12.10, Ubuntu 12.04 LTS, Ubuntu 11.10, Ubuntu 10.04 LTS, and Ubuntu 8.04 LTS operating systems.According to Canonical, several security issues have been fixed in PostgreSQL.
For example, it was discovered that PostgreSQL incorrectly handled certain connection requests containing database names starting with a dash. A remote attacker could have used this flaw to damage or to destroy files within a server's data directory.
The security flaws can be fixed if you upgrade your system(s) to the latest PostgreSQL package, specific to each distribution. To apply the update, run the Update Manager application.
In general, a standard system update will make all the necessary changes. A system restart will not be necessary to implement the changes.