Debian: DSA-2501-1: xen security update
Summary
Several vulnerabilities were discovered in Xen, a hypervisor.
CVE-2012-0217
Xen does not properly handle uncanonical return addresses on
Intel amd64 CPUs, allowing amd64 PV guests to elevate to
hypervisor privileges. AMD processors, HVM and i386 guests
are not affected.
CVE-2012-0218
Xen does not properly handle SYSCALL and SYSENTER instructions
in PV guests, allowing unprivileged users inside a guest
system to crash the guest system.
CVE-2012-2934
Xen does not detect old AMD CPUs affected by AMD Erratum #121.
For CVE-2012-2934, Xen refuses to start domUs on affected systems
unless the "allow_unsafe" option is passed.
For the stable distribution (squeeze), these problems have been fixed
in version 4.0.1-5.2.
For the testing distribution (wheezy) and the unstable distribution
(sid), these problems have been fixed in version
4.1.3~rc1+hg-20120614.a9c0a89c08f2-1.
We recommend that you upgrade your xen packages.
Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at: http://www.debian.org/security/
Mailing list: debian-security-announce@lists.debian.org