The xen packages contain administration tools and the xend service formanaging the kernel-xen kernel for virtualization on Red Hat EnterpriseLinux.It was found that the xc_try_bzip2_decode() and xc_try_lzma_decode() decoderoutines did not correctly check for a possible buffer size overflow in thedecoding loop. As well, several integer overflow flaws and missingerror/range checking were found that could lead to an infinite loop. Aprivileged guest user could use these flaws to crash the guest or,possibly, execute arbitrary code in the privileged management domain(Dom0). (CVE-2011-1583)All xen users are advised to upgrade to these updated packages, whichcontain backported patches to correct these issues. The system must berebooted for this update to take effect.