Xen Hypervisor Security Advisory

Number: AV15-103
Date: 29 October 2015


The purpose of this advisory is to bring attention to the recently released update for Xen.


Xen has released a security update to address a critical security bug in the hypervisor code handling memory virtualization for paravirtualized (PV) systems. As a result of the vulnerability, a malicious paravirtualized guest could break out of its confined isolation and run code at kernel privilege.

Affected versions :
Xen 4.3.x
Xen 4.4.x
Xen 4.5.x
Xen 4.6.x

CVE Reference: CVE-2015-7835

Suggested Action

CCIRC recommends that owner/operators test and deploy the vendor released updates or workarounds to affected platforms accordingly.



Note to Readers

In support of Public Safety's mission to build a safe and resilient Canada, CCIRC's mandate is to help ensure the security and resilience of the vital non-federal government cyber systems that underpin Canada's national security, public safety and economic prosperity. As Canada's computer security incident response team, CCIRC is Canada's national coordination centre for the prevention and mitigation of, preparedness for, response to, and recovery from cyber incidents on non-federal government systems. It does this by providing authoritative advice and support, and coordinating information sharing and incident response.

Please note, CCIRC PGP key has recently been updated.

For general information, please contact Public Safety Canada's Public Affairs division at:

Telephone: 613-944-4875 or 1-800-830-3118
Fax: 613-998-9589
E-mail: ps.communications-communications.sp@canada.ca

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