A flaw in dhcpcd’s IPv6 Router Advertisement handling allows an attacker to craft a packet containing a zero‑length Neighbor Discovery option. The packet bypasses initial validation, and when the client later parses it, a loop that never advances consumes CPU cycles indefinitely, leading to a denial‑of‑service condition characterized by excessive processor usage. The weakness is catalogued as CWE‑835, indicating an incorrect loop/termination condition.

The vulnerability affects Red Hat Enterprise Linux 10 systems that ship the stock dhcpcd package. All installations of dhcpcd on RHEL 10 are vulnerable; no sub‑version boundaries are specified. The issue is limited to the RHEL 10 distribution, as the patched package will only be available for that platform.

The CVSS score of 6.5 indicates a medium severity exploit. The EPSS score of less than 1% shows a very low but non‑zero likelihood of exploitation, and the vulnerability is not listed in the CISA KEV catalog. The likely attack vector is network‑based: an adversary who can inject ICMPv6 Router Advertisements onto an interface that accepts them can trigger the denial‑of‑service. The attack requires the target to process Router Advertisements, so disabling or filtering these packets removes the attack surface.