Debian: DSA-2544-1: xen security update
Summary
Multiple denial of service vulnerabilities have been discovered in xen,
an hypervisor. The Common Vulnerabilities and Exposures project identifies
the following problems:
CVE-2012-3494:
It was discovered that set_debugreg allows writes to reserved bits
of the DR7 debug control register on amd64 (x86-64) paravirtualised
guests, allowing a guest to crash the host.
CVE-2012-3496:
Matthew Daley discovered that XENMEM_populate_physmap, when called
with the MEMF_populate_on_demand flag set, a BUG (detection routine)
can be triggered if a translating paging mode is not being used,
allowing a guest to crash the host.
For the stable distribution (squeeze), these problems have been fixed in
version 4.0.1-5.4.
For the testing distribution (wheezy), these problems will be fixed
soon.
For the unstable distribution (sid), these problems have been fixed in
version 4.1.3-2.
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