Several security issues were fixed in the kernel.
A flaw was discovered in the automatic loading of modules in the crypto subsystem of the Linux kernel. A local user could exploit this flaw to load installed kernel modules, increasing the attack surface and potentially using this to gain administrative privileges. (CVE-2013-7421)
24 March 2015
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in the kernel.
A flaw was discovered in the automatic loading of modules in the crypto subsystem of the Linux kernel. A local user could exploit this flaw to load installed kernel modules, increasing the attack surface and potentially using this to gain administrative privileges. (CVE-2013-7421)
A flaw was discovered in the crypto subsystem when screening module names for automatic module loading if the name contained a valid crypto module name, eg. vfat(aes). A local user could exploit this flaw to load installed kernel modules, increasing the attack surface and potentially using this to gain administrative privileges. (CVE-2014-9644)
Sun Baoliang discovered a use after free flaw in the Linux kernel’s SCTP (Stream Control Transmission Protocol) subsystem during INIT collisions. A remote attacker could exploit this flaw to cause a denial of service (system crash) or potentially escalate their privileges on the system. (CVE-2015-1421)
Marcelo Leitner discovered a flaw in the Linux kernel’s routing of packets to too many different dsts/too fast. A remote attacker can exploit this flaw to cause a denial of service (system crash). (CVE-2015-1465)
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.
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.