PostgreSQL is an advanced object-relational database management system . A stack-based buffer overflow flaw was found in the way PostgreSQL processed certain tokens from an SQL query when the intarray module was enabled on a particular database. An authenticated database user running a specially-crafted SQL query could use this flaw to cause a temporary denial of service or, potentially, execute arbitrary code with the privileges of the database server. Red Hat would like to thank Geoff Keating of the Apple Product Security team for reporting this issue. For Red Hat Enterprise Linux 4, the updated postgresql packages contain a backported patch for this issue; there are no other changes. For Red Hat Enterprise Linux 5, the updated postgresql packages upgrade PostgreSQL to version 8.1.23, and contain a backported patch for this issue. If the postgresql service is running, it will be automatically restarted after installing this update.