CVE-2017-17449

La función __netlink_deliver_tap_skb en net/netlink/af_netlink.c en el kernel de Linux hasta la versión 4.14.4, cuando CONFIG_NLMON está habilitado, no restringe las observaciones de mensajes Netlink a un espacio de nombres de red único, lo que permite que usuarios locales obtengan información sensible utilizando la capacidad CAP_NET_ADMIN para rastrear una interfaz nlmon para toda la actividad Netlink en el sistema.

The __netlink_deliver_tap_skb function in net/netlink/af_netlink.c in the Linux kernel, through 4.14.4, does not restrict observations of Netlink messages to a single net namespace, when CONFIG_NLMON is enabled. This allows local users to obtain sensitive information by leveraging the CAP_NET_ADMIN capability to sniff an nlmon interface for all Netlink activity on the system.

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. Jan H. Schonherr discovered that the Xen subsystem did not properly handle block IO merges correctly in some situations. An attacker in a guest vm could use this to cause a denial of service or possibly gain administrative privileges in the host. Various other issues were also addressed.