CVE-2017-2618

Se ha encontrado un fallo en el manejo del kernel de Linux para borrar los atributos SELinux de los ficheros /proc/pid/attr en versiones anteriores a la 4.9.10. Una escritura vacía (null) en este archivo puede cerrar de manera inesperada el sistema haciendo que el sistema intente acceder a la memoria no mapeada del kernel.

A flaw was found in the Linux kernel's handling of clearing SELinux attributes on /proc/pid/attr files. An empty (null) write to this file can crash the system by causing the system to attempt to access unmapped kernel memory.

USN-3358-1 fixed vulnerabilities in the Linux kernel for Ubuntu 17.04. This update provides the corresponding updates for the Linux Hardware Enablement kernel from Ubuntu 17.04 for Ubuntu 16.04 LTS. Please note that this update changes the Linux HWE kernel to the 4.10 based kernel from Ubuntu 17.04, superseding the 4.8 based HWE kernel from Ubuntu 16.10. Ben Harris discovered that the Linux kernel would strip extended privilege attributes of files when performing a failed unprivileged system call. A local attacker could use this to cause a denial of service. Various other issues were also addressed.