Several security issues were fixed in the kernel.
Vadim Ponomarev discovered a flaw in the Linux kernel causing a reference leak when PID namespaces are used. A remote attacker could exploit this flaw causing a denial of service. (CVE-2012-2127)
3 October 2012
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in the kernel.
Vadim Ponomarev discovered a flaw in the Linux kernel causing a reference leak when PID namespaces are used. A remote attacker could exploit this flaw causing a denial of service. (CVE-2012-2127)
A flaw was found in how the Linux kernel’s KVM (Kernel-based Virtual Machine) subsystem handled MSI (Message Signaled Interrupts). A local unprivileged user could exploit this flaw to cause a denial of service or potentially elevate privileges. (CVE-2012-2137)
Mathias Krause discover an error in Linux kernel’s Datagram Congestion Control Protocol (DCCP) Congestion Control Identifier (CCID) use. A local attack could exploit this flaw to cause a denial of service (crash) and potentially escalate privileges if the user can mmap page 0. (CVE-2013-1827)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to reboot your computer to make all the necessary changes.