cve-2026-44608

CVE-2026-44608 is a denial-of-service vulnerability in NLnet Labs Unbound versions 1.14.0 through 1.25.0, disclosed in May 2026. The flaw can be triggered under specific multi-threaded Response Policy Zone transfer conditions, causing a crash. It is fixed in Unbound 1.25.1. While not a Windows kernel flaw or a typical Microsoft Patch Tuesday issue, this vulnerability is relevant to Windows network administrators because Unbound is often used as a DNS resolver in Windows environments. A crash in this open-source DNS software can lead to widespread network outages, making it a critical stability concern for Windows networks that rely on it.