Debian Linux Security Advisory 2582-1 - Multiple denial of service vulnerabilities have been discovered in the xen hypervisor. One of the issues (CVE-2012-5513) could even lead to privilege escalation from guest to host.
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Red Hat Security Advisory 2011-1386-01 - The kernel packages contain the Linux kernel, the core of any Linux operating system. The maximum file offset handling for ext4 file systems could allow a local, unprivileged user to cause a denial of service. IPv6 fragment identification value generation could allow a remote attacker to disrupt a target system's networking, preventing legitimate users from accessing its services. Various other issues in the kernel have also been addressed.
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