Ubuntu Security Notice 2965-2 – USN-2965-1 fixed vulnerabilities in the Linux kernel for Ubuntu 16.04 LTS. This update provides the corresponding updates for the Linux Hardware Enablement (HWE) kernel from Ubuntu 16.04 LTS for Ubuntu 14.04 LTS. Jann Horn discovered that the extended Berkeley Packet Filter (eBPF) implementation in the Linux kernel did not properly reference count file descriptors, leading to a use-after-free. A local unprivileged attacker could use this to gain administrative privileges. Various other issues were also addressed.