CVE-2019-5598

n FreeBSD 11.3-PRERELEASE antes de r345378, 12.0-ESTABLE antes de r345377, 11.2-RELEASE antes de 11.2-RELEASE-p10, y 12.0-RELEASE antes de 12.0-RELEASE-p4, un error en pf no verifica si el paquete ICMP exterior o ICMP6 tiene la misma IP de destino que la IP de la fuente del paquete de protocolo interno permitiendo la creación maliciosa de un paquete ICMP / ICMP6 podría eludir las reglas de el Packet Filter y pasar a un host que de lo contrario estará inhabilitado.

States in pf(4) let ICMP and ICMP6 packets pass if they have a packet in their payload matching an existing condition. pf(4) does not check if the outer ICMP or ICMP6 packet has the same destination IP as the source IP of the inner protocol packet. A maliciously crafted ICMP/ICMP6 packet could bypass the packet filter rules and be passed to a host that would otherwise be unavailable.