An update for Xen was just released to address two major security vulnerabilities and it is recommended that you update as soon as possible.
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Numerous updates were just released to address various security vulnerabilities and it is recommended that you update as soon as possible. (XSA-145 to XSA-153) Official Link: http://xenbits.xen.org/xsa/ Source: Hostingseclist
An update for Xen was just released to address a vulnerability where a buggy or malicious HVM guest can crash the host or read data relating to other guests or the hypervisor itself. source:hostingseclist