Linux kernel 2.6.18, and possibly other versions, when running on AMD64 architectures, allows local users to cause a denial of service (crash) via certain ptrace calls.
lists.opensuse.org/opensuse-security-announce/2008-06/msg00006.html
lists.opensuse.org/opensuse-security-announce/2008-07/msg00000.html
lists.opensuse.org/opensuse-security-announce/2008-07/msg00002.html
lists.opensuse.org/opensuse-security-announce/2008-07/msg00007.html
lists.opensuse.org/opensuse-security-announce/2008-07/msg00012.html
secunia.com/advisories/30112
secunia.com/advisories/30252
secunia.com/advisories/30294
secunia.com/advisories/30368
secunia.com/advisories/30818
secunia.com/advisories/30890
secunia.com/advisories/30962
secunia.com/advisories/30982
secunia.com/advisories/31107
secunia.com/advisories/31628
www.debian.org/security/2008/dsa-1588
www.mandriva.com/security/advisories?name=MDVSA-2008:167
www.mandriva.com/security/advisories?name=MDVSA-2008:174
www.redhat.com/support/errata/RHSA-2008-0237.html
www.redhat.com/support/errata/RHSA-2008-0275.html
www.redhat.com/support/errata/RHSA-2008-0585.html
www.securityfocus.com/bid/29086
www.securitytracker.com/id?1020047
www.ubuntu.com/usn/usn-625-1
bugzilla.redhat.com/show_bug.cgi?id=431430
exchange.xforce.ibmcloud.com/vulnerabilities/42278
oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A9563
www.redhat.com/archives/fedora-package-announce/2008-May/msg00357.html