Ubuntu Update for linux USN-1796-1

Solution
Please Install the Updated Packages.
Insight
Andrew Jones discovered a flaw with the xen_iret function in Linux kernel's Xen virtualizeation. In the 32-bit Xen paravirt platform an unprivileged guest OS user could exploit this flaw to cause a denial of service (crash the system) or gain guest OS privilege. (CVE-2013-0228) Emese Revfy discovered that in the Linux kernel signal handlers could leak address information across an exec, making it possible to by pass ASLR (Address Space Layout Randomization). A local user could use this flaw to by pass ASLR to reliably deliver an exploit payload that would otherwise be stopped (by ASLR). (CVE-2013-0914) A memory use after free error was discover in the Linux kernel's tmpfs filesystem. A local user could exploit this flaw to gain privileges or cause a denial of service (system crash). (CVE-2013-1767) Mateusz Guzik discovered a race in the Linux kernel's keyring. A local user could exploit this flaw to cause a denial of service (system crash). (CVE-2013-1792) Mathias Krause discovered a memory leak in the Linux kernel's crypto report API. A local user with CAP_NET_ADMIN could exploit this leak to examine some of the kernel's stack memory. (CVE-2013-2546) Mathias Krause discovered a memory leak in the Linux kernel's crypto report API. A local user with CAP_NET_ADMIN could exploit this leak to examine some of the kernel's heap memory. (CVE-2013-2547) Mathias Krause discovered information leaks in the Linux kernel's crypto algorithm report API. A local user could exploit these flaws to leak kernel stack and heap memory contents. (CVE-2013-2548)
Affected
linux on Ubuntu 12.10