postgresql is vulnerable to privilege escalation. The vulnerability exists as it was discovered that a user could utilize the features of the PL/Perl and PL/Tcl languages to modify the behavior of a SECURITY DEFINER function created by a different user. If the PL/Perl or PL/Tcl language was used to implement a SECURITY DEFINER function, an authenticated database user could use a PL/Perl or PL/Tcl script to modify the behavior of that function during subsequent calls in the same session. This would result in the modified or injected code also being executed with the privileges of the user who created the SECURITY DEFINER function, possibly leading to privilege escalation.
kb.juniper.net/InfoCenter/index?page=content&id=JSA10705
lists.fedoraproject.org/pipermail/package-announce/2010-October/049591.html
lists.fedoraproject.org/pipermail/package-announce/2010-October/049592.html
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lists.opensuse.org/opensuse-security-announce/2010-11/msg00001.html
marc.info/?l=bugtraq&m=134124585221119&w=2
secunia.com/advisories/42325
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www.redhat.com/security/updates/classification/#moderate
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www.redhat.com/support/errata/RHSA-2010-0908.html
www.securityfocus.com/bid/43747
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bugzilla.redhat.com/show_bug.cgi?id=639371
oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A7291