Stack-based buffer overflow in the get_matching_model_microcode function in arch/x86/kernel/cpu/microcode/intel_early.c in the Linux kernel before 4.0 allows context-dependent attackers to gain privileges by constructing a crafted microcode header and leveraging root privileges for write access to the initrd.

Affected: Ubuntu:14.04:LTS: linux

A stack overflow was discovered in the the microcode loader for the intel x86 platform. A local attacker could exploit this flaw to cause a denial of service (kernel crash) or to potentially execute code with kernel privileges. (CVE-2015-2666)

It was discovered that the Linux kernel's IPv6 networking stack has a flaw that allows using route advertisement (RA) messages to set the 'hop_limit' to values that are too low. An unprivileged attacker on a local network could exploit this flaw to cause a denial of service (IPv6 messages dropped). (CVE-2015-2922)