CVE-2007-3731 Information

Description

The Linux kernel 2.6.20 and 2.6.21 does not properly handle an invalid LDT segment selector in cs (the xcs field) during ptrace single-step operations which allows local users to cause a denial of service (NULL dereference and OOPS) via certain code that makes ptrace PTRACE_SETREGS and PTRACE_SINGLESTEP requests related to the TRACE_IRQS_ON function and possibly related to the arch_ptrace function.

Reference

http://bugzilla.kernel.org/show_bug.cgi?id=8765 http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=29eb51101c02df517ca64ec472d7501127ad1da8 http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=a10d9a71bafd3a283da240d2868e71346d2aef6f http://osvdb.org/37286 http://secunia.com/advisories/26935 http://secunia.com/advisories/26955 http://secunia.com/advisories/26978 http://secunia.com/advisories/27322 http://secunia.com/advisories/29159 http://wiki.rpath.com/wiki/Advisories:rPSA-2008-0094 http://www.debian.org/security/2007/dsa-1378 http://www.redhat.com/support/errata/RHSA-2007-0940.html http://www.securityfocus.com/archive/1/488972/100/0/threaded http://www.securityfocus.com/bid/25801 http://www.ubuntu.com/usn/usn-518-1 https://bugzilla.redhat.com/show_bug.cgi?id=248324 https://issues.rpath.com/browse/RPL-2304 https://oval.cisecurity.org/repository/search/definition/oval3Aorg.mitre.oval3Adef3A10394