{"id":"DEBIAN-CVE-2026-54478","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":"2026-09-29T13:04:03.011190006Z","published":"2026-07-22T14:17:21.177Z","upstream":["CVE-2026-54478"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-54478"}],"affected":[{"package":{"name":"unbound","ecosystem":"Debian:12","purl":"pkg:deb/debian/unbound?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.17.1-2","1.17.1-2+deb12u1","1.17.1-2+deb12u2","1.17.1-2+deb12u3","1.17.1-2+deb12u4","1.17.1-2+loong64","1.18.0-1","1.18.0-2","1.19.1-1","1.19.2-1","1.20.0-1","1.21.1-1","1.22.0-1","1.22.0-2","1.23.1-1","1.24.0-1","1.24.0-2","1.24.1-1","1.24.1-2","1.24.2-1","1.25.0-1","1.25.1-1","1.25.2-1","1.26.0-1","1.26.0-2","1.26.1-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-54478.json"}},{"package":{"name":"unbound","ecosystem":"Debian:13","purl":"pkg:deb/debian/unbound?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.26.1-0+deb13u1"}]}],"versions":["1.22.0-2","1.22.0-2+deb13u1","1.22.0-2+deb13u2","1.22.0-2+deb13u3","1.23.1-1","1.24.0-1","1.24.0-2","1.24.1-1","1.24.1-2","1.24.2-1","1.25.0-1","1.25.1-1","1.25.2-1","1.26.0-1","1.26.0-2"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-54478.json"}},{"package":{"name":"unbound","ecosystem":"Debian:14","purl":"pkg:deb/debian/unbound?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.25.2-1"}]}],"versions":["1.22.0-2","1.23.1-1","1.24.0-1","1.24.0-2","1.24.1-1","1.24.1-2","1.24.2-1","1.25.0-1","1.25.1-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-54478.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N"}]}