Several local vulnerabilities have been discovered in PostgreSQL, an object-relational SQL database. The Common Vulnerabilities and Exposures project identifies the following problems: It was discovered that the DBLink module performed insufficient credential validation. This issue is also tracked as CVE-2007-6601, since the initial upstream fix was incomplete. Tavis Ormandy and Will Drewry discovered that a bug in the handling of back-references inside the regular expressions engine could lead to an out of bounds read, resulting in a crash. This constitutes only a security problem if an application using PostgreSQL processes regular expressions from untrusted sources. Tavis Ormandy and Will Drewry discovered that the optimizer for regular expression could be tricked into an infinite loop, resulting in denial of service. This constitutes only a security problem if an application using PostgreSQL processes regular expressions from untrusted sources. Tavis Ormandy and Will Drewry discovered that the optimizer for regular expression could be tricked massive resource consumption. This constitutes only a security problem if an application using PostgreSQL processes regular expressions from untrusted sources. Functions in index expressions could lead to privilege escalation. For a more in depth explanation please see the upstream announce available at http://www.postgresql.org/about/news.905. For the old stable distribution (sarge), some of these problems have been fixed in version 7.4.7-6sarge6 of the postgresql package. Please note that the fix for CVE-2007-6600 and for the handling of regular expressions havn't been backported due to the intrusiveness of the fix. We recommend to upgrade to the stable distribution if these vulnerabilities affect your setup. For the stable distribution (etch), these problems have been fixed in version 7.4.19-0etch1. The unstable distribution (sid) no longer contains postgres-7.4. We recommend that you upgrade your postgresql-7.4 packages.