CVE-2017-7518

Se ha detectado un error en el kernel de Linux en versiones anteriores a la 4.12 en la forma en la que el módulo KVM procesó el bit trap flag(TF) en EFLAGS durante la emulación de la instrucción de la llamada del sistema, lo que conduce a que se lance una excepción de depuración (#DB) en la pila invitada. Un usuario/proceso en un invitado podría utilizar este error para escalar sus privilegios en el invitado. Los invitados de Linux no se han visto afectados por esto.

A flaw was found in the way the Linux KVM module processed the trap flag(TF) bit in EFLAGS during emulation of the syscall instruction, which leads to a debug exception(#DB) being raised in the guest stack. A user/process inside a guest could use this flaw to potentially escalate their privileges inside the guest. Linux guests are not affected by this.

Jann Horn discovered that the Berkeley Packet Filter implementation in the Linux kernel improperly performed sign extension in some situations. A local attacker could use this to cause a denial of service or possibly execute arbitrary code. It was discovered that a race condition leading to a use-after-free vulnerability existed in the ALSA PCM subsystem of the Linux kernel. A local attacker could use this to cause a denial of service or possibly execute arbitrary code. Various other issues were also addressed.