Off-by-one error in the flask_security_avc_cachestats function in xsm/flask/flask_op.c in Xen 4.2.x and 4.3.x, when the maximum number of physical CPUs are in use, allows local users to cause a denial of service (host crash) or obtain sensitive information from hypervisor memory by leveraging a FLASK_AVC_CACHESTAT hypercall, which triggers a buffer over-read.
http://xenbits.xen.org/xsa/advisory-85.html
http://www.openwall.com/lists/oss-security/2014/02/10/6
http://www.openwall.com/lists/oss-security/2014/02/07/12
http://security.gentoo.org/glsa/glsa-201407-03.xml
http://lists.opensuse.org/opensuse-security-announce/2014-03/msg00011.html