USN-3594-1

USN-3542-1 mitigated CVE-2017-5715 (Spectre Variant 2) for the amd64 architecture in Ubuntu 14.04 LTS. This update provides the compiler-based retpoline kernel mitigation for the amd64 and i386 architectures. Original advisory details:

Jann Horn discovered that microprocessors utilizing speculative execution and branch prediction may allow unauthorized memory reads via sidechannel attacks. This flaw is known as Spectre. A local attacker could use this to expose sensitive information, including kernel memory. (CVE-2017-5715)