CVE-2026-93009

Name of the Vulnerable Software and Affected Versions dnsmasq versions prior to 2.93-3.1

Description A flaw exists in the DHCPv6 client hostname parser that allows it to read one byte past the end of a crafted Fully Qualified Domain Name (FQDN) option. This occurs because the parser checks the next label length before confirming the pointer remains within the option boundaries. A local network attacker can trigger this behavior using a single DHCPv6 packet. The extra byte is neither returned to the client nor logged, and no crash has been demonstrated.

Recommendations Update to version 2.93-3.1.