The __secure_computing function in kernel/seccomp.c in the seccomp subsystem in the Linux kernel 2.6.28.7 and earlier on the x86_64 platform, when CONFIG_SECCOMP is enabled, does not properly handle (1) a 32-bit process making a 64-bit syscall or (2) a 64-bit process making a 32-bit syscall, which allows local users to bypass intended access restrictions via crafted syscalls that are misinterpreted as (a) stat or (b) chmod, a related issue to CVE-2009-0342 and CVE-2009-0343.
http://www.ubuntu.com/usn/usn-751-1
http://www.securityfocus.com/bid/33948
http://www.redhat.com/support/errata/RHSA-2009-0451.html
http://www.mandriva.com/security/advisories?name=MDVSA-2009:118
http://www.debian.org/security/2009/dsa-1800
http://secunia.com/advisories/35394
http://secunia.com/advisories/35390
http://secunia.com/advisories/35185
http://secunia.com/advisories/35121
http://secunia.com/advisories/34917
http://secunia.com/advisories/34786
http://secunia.com/advisories/34084
http://scarybeastsecurity.blogspot.com/2009/02/linux-kernel-minor-seccomp.html
http://scary.beasts.org/security/CESA-2009-004.html
http://marc.info/?l=oss-security&m=123597627132485&w=2
http://marc.info/?l=linux-kernel&m=123579056530191&w=2
http://lkml.org/lkml/2009/2/28/23
http://lists.opensuse.org/opensuse-security-announce/2009-06/msg00001.html
http://lists.opensuse.org/opensuse-security-announce/2009-06/msg00000.html
http://lists.opensuse.org/opensuse-security-announce/2009-05/msg00002.html
http://lists.opensuse.org/opensuse-security-announce/2009-04/msg00007.html