ASA-2019-00504 – Wind River VxWorks: Logical flaw in IPv4 assignment by the ipdhcpc DHCP client

The VxWorks DHCP client fails to properly validate that the offered IP-address in a DHCP renewal or offer response contains a valid unicast address. An attacker may assign multicast or broadcast addresses to the victim. An attacker residing on the LAN may choose to highjack a DHCP-client session that requests an IPv4 address. The attacker can send a multicast IP address in the DHCP offer/ack message, which the victim system then incorrectly assigns. This vulnerability is not very useful in isolation, but can be combined with CVE-2019-12259 to create a denial-ofservice attack.