PostgreSQL project reports:
The PostgreSQL Global Development Group has released a security update to all current versions of the PostgreSQL database system, including versions 9.2.4, 9.1.9, 9.0.13, and 8.4.17. This update fixes a high-exposure security vulnerability in versions 9.0 and later. All users of the affected versions are strongly urged to apply the update *immediately*. A major security issue (for versions 9.x only) fixed in this release, [CVE-2013-1899](http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-1899), makes it possible for a connection request containing a database name that begins with "-" to be crafted that can damage or destroy files within a server's data directory. Anyone with access to the port the PostgreSQL server listens on can initiate this request. This issue was discovered by Mitsumasa Kondo and Kyotaro Horiguchi of NTT Open Source Software Center. Two lesser security fixes are also included in this release: [CVE-2013-1900](http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-1900), wherein random numbers generated by contrib/pgcrypto functions may be easy for another database user to guess (all versions), and [CVE-2013-1901](http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-1901), which mistakenly allows an unprivileged user to run commands that could interfere with in-progress backups (for versions 9.x only).