{"id":"DEBIAN-CVE-2026-123603","details":"hickory-proto and hickory-resolver 0.26.0 before 0.26.2, hickory-server 0.25.0-alpha.1 before 0.26.2, and hickory-recursor 0.25.0-alpha.3 through 0.26.0-alpha.1 fail to canonicalize IPv4-mapped IPv6 addresses when checking deny_answers, deny_server, or AccessControlSet rules. Attackers can use IPv4-mapped addresses to evade answer filtering, trigger queries to denied nameservers, or reach hickory-server library deployments on dual-stack IPv6 sockets from denied clients.","modified":"2026-11-08T16:00:07.051447742Z","published":"2026-11-08T02:16:55.117Z","upstream":["CVE-2026-123603"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-123603"}],"affected":[{"package":{"name":"rust-hickory-proto","ecosystem":"Debian:13","purl":"pkg:deb/debian/rust-hickory-proto?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.24.4-2","0.24.4-3","0.24.4-4","0.24.4-4.1","0.24.4-5","0.24.4-6","0.25.2-1","0.25.2-2","0.25.2-3","0.26.1-1","0.26.3-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-123603.json"}},{"package":{"name":"rust-hickory-proto","ecosystem":"Debian:14","purl":"pkg:deb/debian/rust-hickory-proto?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.26.3-1"}]}],"versions":["0.24.4-2","0.24.4-3","0.24.4-4","0.24.4-4.1","0.24.4-5","0.24.4-6","0.25.2-1","0.25.2-2","0.25.2-3","0.26.1-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-123603.json"}},{"package":{"name":"rust-hickory-recursor","ecosystem":"Debian:13","purl":"pkg:deb/debian/rust-hickory-recursor?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.24.1-1","0.25.2-1","0.25.2-2","0.25.2-3","0.25.2-4","0.25.2-5","0.25.2-6"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-123603.json"}},{"package":{"name":"rust-hickory-recursor","ecosystem":"Debian:14","purl":"pkg:deb/debian/rust-hickory-recursor?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.24.1-1","0.25.2-1","0.25.2-2","0.25.2-3","0.25.2-4","0.25.2-5","0.25.2-6"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-123603.json"}},{"package":{"name":"rust-hickory-resolver","ecosystem":"Debian:13","purl":"pkg:deb/debian/rust-hickory-resolver?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.24.4-1","0.24.4-2","0.24.4-3","0.24.4-4","0.24.4-5","0.25.2-1","0.25.2-2","0.26.1-1","0.26.3-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-123603.json"}},{"package":{"name":"rust-hickory-resolver","ecosystem":"Debian:14","purl":"pkg:deb/debian/rust-hickory-resolver?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.26.3-1"}]}],"versions":["0.24.4-1","0.24.4-2","0.24.4-3","0.24.4-4","0.24.4-5","0.25.2-1","0.25.2-2","0.26.1-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-123603.json"}},{"package":{"name":"rust-hickory-server","ecosystem":"Debian:13","purl":"pkg:deb/debian/rust-hickory-server?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.24.4-2","0.25.2-1","0.25.2-2","0.25.2-3","0.25.2-4","0.26.1-1","0.26.1-2","0.26.3-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-123603.json"}},{"package":{"name":"rust-hickory-server","ecosystem":"Debian:14","purl":"pkg:deb/debian/rust-hickory-server?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.26.3-1"}]}],"versions":["0.24.4-2","0.25.2-1","0.25.2-2","0.25.2-3","0.25.2-4","0.26.1-1","0.26.1-2"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-123603.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N"}]}