Microsoft has listed CVE-2026-42923, disclosed on May 20, 2026, as a degradation-of-service flaw in NLnet Labs Unbound, where vulnerable DNSSEC validation can spend excessive time on NSEC3 hash calculations and intermittently reduce resolver availability under attacker-controlled conditions. The...
CVE-2026-42923 is a medium-severity DNSSEC validation flaw disclosed in May 2026 affecting NLnet Labs Unbound through version 1.25.0, where specially crafted NSEC3 records can force excessive hash calculations and degrade resolver availability over the network. It is not the sort of bug that...