CVE-2014-7155 Information

Description

The x86_emulate function in arch/x86/x86_emulate/x86_emulate.c in Xen 4.4.x and earlier does not properly check supervisor mode permissions which allows local HVM users to cause a denial of service (guest crash) or gain guest kernel mode privileges via vectors involving an (1) HLT (2) LGDT (3) LIDT or (4) LMSW instruction.

Reference

http://lists.fedoraproject.org/pipermail/package-announce/2014-October/140418.html http://lists.fedoraproject.org/pipermail/package-announce/2014-October/140483.html http://lists.opensuse.org/opensuse-security-announce/2014-10/msg00002.html http://lists.opensuse.org/opensuse-security-announce/2014-10/msg00003.html http://secunia.com/advisories/61858 http://secunia.com/advisories/61890 http://security.gentoo.org/glsa/glsa-201412-42.xml http://support.citrix.com/article/CTX200218 http://www.debian.org/security/2014/dsa-3041 http://www.securityfocus.com/bid/70057 http://www.securitytracker.com/id/1030888 http://xenbits.xen.org/xsa/advisory-105.html