USN-2779-1: Linux kernel vulnerabilities
20 October 2015
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 15.04
Several security issues were fixed in the kernel.
- linux - Linux kernel
It was discovered that the Linux kernel did not check if a new IPv6 MTU set by a user space application was valid. A remote attacker could forge a route advertisement with an invalid MTU that a user space daemon like NetworkManager would honor and apply to the kernel, causing a denial of service. (CVE-2015-0272)
It was discovered that virtio networking in the Linux kernel did not handle fragments correctly, leading to kernel memory corruption. A remote attacker could use this to cause a denial of service (system crash) or possibly execute code with administrative privileges. (CVE-2015-5156)
It was discovered that the Reliable Datagram Sockets (RDS) implementation in the Linux kernel did not verify sockets were properly bound before attempting to send a message, which could cause a NULL pointer dereference. An attacker could use this to cause a denial of service (system crash). (CVE-2015-6937)
Ben Hutchings discovered that the Advanced Union Filesystem (aufs) for the Linux kernel did not correctly handle references of memory mapped files from an aufs mount. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code with administrative privileges. (CVE-2015-7312)
The problem can be corrected by updating your system to the following package versions:
- Ubuntu 15.04
- linux-image-3.19.0-31-generic - 3.19.0-31.36
- linux-image-3.19.0-31-generic-lpae - 3.19.0-31.36
- linux-image-3.19.0-31-lowlatency - 3.19.0-31.36
- linux-image-3.19.0-31-powerpc-e500mc - 3.19.0-31.36
- linux-image-3.19.0-31-powerpc-smp - 3.19.0-31.36
- linux-image-3.19.0-31-powerpc64-emb - 3.19.0-31.36
- linux-image-3.19.0-31-powerpc64-smp - 3.19.0-31.36
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.
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.