{"id":"AZL-92958","summary":"CVE-2026-54478 affecting package unbound for versions less than 1.25.2-1","details":"In NLnet Labs Unbound 1.18.0 up to and including 1.25.1, when Unbound listens on a 'proxy-protocol-port' interface with 'answer-cookie: yes', the RFC 9018 server-cookie SipHash is computed over the proxy's wire address instead of the PROXYv2-declared client. One server cookie obtained through a given proxy node therefore validates for every PROXYv2-declared source behind that node. On a UDP+proxy-protocol front, an off-path attacker can harvest one cookie with a single legitimate query, then replay it under any spoofed source and pass DNS Cookie checks that were deployed to defeat this in the first place.","modified":"2026-08-28T17:47:18.626425219Z","published":"2026-07-22T14:17:21Z","upstream":["CVE-2026-54478"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-54478"}],"affected":[{"package":{"name":"unbound","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/unbound"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.25.2-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-92958.json"}}],"schema_version":"1.9.0"}