============================================================================ Ubuntu Security Notice USN-2701-1 July 31, 2015 linux-lts-trusty vulnerabilities ============================================================================ A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 12.04 LTS Summary: Several security issues were fixed in the kernel. Software Description: - linux-lts-trusty: Linux hardware enablement kernel from Trusty Details: Andy Lutomirski discovered a flaw in the Linux kernel's handling of nested NMIs (non-maskable interrupts). An unprivileged local user could exploit this flaw to cause a denial of service (system crash) or potentially escalate their privileges. (CVE-2015-3290) Andy Lutomirski discovered a flaw that allows user to cause the Linux kernel to ignore some NMIs (non-maskable interrupts). A local unprivileged user could exploit this flaw to potentially cause the system to miss important NMIs resulting in unspecified effects. (CVE-2015-3291) Andy Lutomirski and Petr Matousek discovered that an NMI (non-maskable interrupt) that interrupts userspace and encounters an IRET fault is incorrectly handled by the Linux kernel. An unprivileged local user could exploit this flaw to cause a denial of service (kernel OOPs), corruption, or potentially escalate privileges on the system. (CVE-2015-5157) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 12.04 LTS: linux-image-3.13.0-61-generic 3.13.0-61.100~precise1 linux-image-3.13.0-61-generic-lpae 3.13.0-61.100~precise1 After a standard system update you need to reboot your computer to make all the necessary changes. ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. If you use linux-restricted-modules, you have to update that package as well to get modules which work with the new kernel version. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-server, linux-powerpc), a standard system upgrade will automatically perform this as well. References: http://www.ubuntu.com/usn/usn-2701-1 CVE-2015-3290, CVE-2015-3291, CVE-2015-5157 Package Information: https://launchpad.net/ubuntu/+source/linux-lts-trusty/3.13.0-61.100~precise1