CVE-2013-0151: nested virtualization on 32-bit exposes host crash When performing nested virtualisation Xen would incorrectly map guest pages for extended periods using an interface which is only intended for transient mappings. In some configurations there are a limited number of slots available for these transient mappings and exhausting them leads to a host crash and therefore a Denial of Service attack. A malicious guest administrator can, by enabling nested virtualisation from within the guest, trigger the issue. CVE-2013-0152: nested HVM exposes host to being driven out of memory by guest Guests are currently permitted to enable nested virtualization on themselves. Missing error handling cleanup in the handling code makes it possible for a guest, particularly a multi-vCPU one, to repeatedly invoke this operation, thus causing a leak of - over time - unbounded amounts of memory. A malicious domain can mount a denial of service attack affecting the whole system. Acknowledgements: Red Hat would like to thank the Xen project for reporting this issue.
Statement: Not vulnerable. This issue did not affect the versions of the kernel-xen package as shipped with Red Hat Enterprise Linux 5. This issue did not affect Red Hat Enterprise Linux 6 and Red Hat Enterprise MRG as we did not have support for Xen hypervisor.
Now public via: http://www.openwall.com/lists/oss-security/2013/01/22/10 http://www.openwall.com/lists/oss-security/2013/01/22/9
Created xen tracking bugs for this issue Affects: fedora-all [bug 902792]
xen-4.2.1-5.fc18 has been pushed to the Fedora 18 stable repository. If problems still persist, please make note of it in this bug report.
Upstream patch for XSA-34 / CVE-2013-0151: http://xenbits.xen.org/gitweb/?p=xen.git;a=commit;h=d60d7082289a74e44b3dc8f67df46c3404ca08bf