CVE-2017-18193

fs/f2fs/extent_cache.c en el kernel de Linux, en versiones anteriores a la 4.13, gestiona de forma incorrecta los árboles extent, lo que permite que usuarios locales provoquen una denegación de servicio (error) mediante una aplicación con múltiples hilos.

USN-3654-1 fixed vulnerabilities and added mitigations in the Linux kernel for Ubuntu 16.04 LTS. This update provides the corresponding updates for the Linux Hardware Enablement kernel from Ubuntu 16.04 LTS for Ubuntu 14.04 LTS. Jann Horn and Ken Johnson discovered that microprocessors utilizing speculative execution of a memory read may allow unauthorized memory reads via a sidechannel attack. This flaw is known as Spectre Variant 4. A local attacker could use this to expose sensitive information, including kernel memory. Various other issues were also addressed.