CVE-2026-41285 affects OpenBSD through version 7.8 in the slaacd and rad daemons. When these daemons receive an ICMPv6 Neighbor Discovery option with a length of zero, they enter an infinite loop because the code evaluates the expression "nd_opt_len * 8 - 2" without first verifying that nd_opt_len is non-zero. This lack of validation leads to improper handling of malformed ND options, resulting in a denial of service condition on the affected daemons.

The vulnerability causes the slaacd and rad daemons to enter an infinite loop upon receiving a crafted ICMPv6 Neighbor Discovery option with zero length. This can lead to denial of service by disrupting these network services on affected OpenBSD systems. There is no indication of remote code execution or privilege escalation. Exploitation requires local network access to send the crafted ICMPv6 packets.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, network administrators should consider limiting ICMPv6 Neighbor Discovery traffic from untrusted sources on local networks to reduce exposure. Monitor vendor channels for updates and apply patches once released.