CVE-2015-7550

La función keyctl_read_key en security/keys/keyctl.c en el kernel de Linux en versiones anteriores a 4.3.4 no utiliza adecuadamente un semáforo, lo que permite a usuarios locales provocar una denegación de servicio (referencia a puntero NULL y caída del sistema) o posiblemente tiene otro impacto no especificado a través de una aplicación manipulada que aprovecha una condición de carrera entre llamadas keyctl_revoke y keyctl_read.

It was discovered that a use-after-free vulnerability existed in the AF_UNIX implementation in the Linux kernel. A local attacker could use crafted epoll_ctl calls to cause a denial of service (system crash) or expose sensitive information. It was discovered that the KVM implementation in the Linux kernel did not properly restore the values of the Programmable Interrupt Timer (PIT). A user-assisted attacker in a KVM guest could cause a denial of service in the host (system crash). Various other issues were also addressed.