{"schemaVersion":3,"id":"CVE-2026-54478","aliases":["ALPINE-CVE-2026-54478","UBUNTU-CVE-2026-54478","DEBIAN-CVE-2026-54478"],"status":"published","duplicateOf":null,"title":null,"description":"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. 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