{"id":"CVE-2026-123603","aliases":[],"cve":{"records":[{"id":"CVE-2026-123603","source":"VulnCheck","state":"PUBLISHED","reasons":[],"replacements":[],"disputed":false,"unsupportedWhenAssigned":false,"reserved":"2026-11-06T01:00:16.506Z","published":"2026-11-08T01:38:30.679Z","modified":"2026-11-13T03:10:51.830Z"}],"publishers":[{"name":"VulnCheck","role":"CNA","organizationId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","modified":"2026-11-08T01:38:30.679Z"},{"name":"CISA-ADP","role":"ADP","organizationId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","modified":"2026-11-13T03:10:51.830Z"}],"references":[{"url":"https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-4jwp-xjwm-333g","tags":["vendor-advisory"],"source":"VulnCheck"},{"url":"https://www.vulncheck.com/advisories/hickory-dns-missing-ipv4-mapped-ipv6-canonicalization-access-control-bypass","tags":["third-party-advisory"],"source":"VulnCheck"}],"weaknesses":[{"id":"CWE-284","description":"Improper Access Control","source":"VulnCheck"}],"applicability":[],"prioritization":[{"source":"CISA-ADP","type":"SSVC","role":"CISA Coordinator","timestamp":"2026-11-13T03:10:41.977245Z","decisions":[{"name":"Exploitation","value":"none"},{"name":"Automatable","value":"yes"},{"name":"Technical Impact","value":"partial"}]}]},"title":"Hickory DNS Missing IPv4-Mapped IPv6 Canonicalization Access Control Bypass","titleSource":"VulnCheck","descriptionSource":"VulnCheck","description":"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clients.","score":6.9,"severity":"medium","published":"2026-11-08T01:38:30.679Z","modified":"2026-11-13T03:10:51.830Z","withdrawn":false,"knownExploited":false,"affected":[],"products":[{"vendor":"hickory-dns","name":"hickory-dns","platforms":[],"versions":[{"version":"0.25.0-alpha.3","status":"affected","lessThanOrEqual":"0.26.0-alpha.1","versionType":"semver"}],"defaultStatus":"unaffected","packageURL":"pkg:cargo/hickory-recursor","packageIdentity":{"ecosystem":"crates.io","name":"hickory-recursor"},"cpes":[],"source":"VulnCheck","url":"https://www.cve.org/CVERecord?id=CVE-2026-123603"},{"vendor":"hickory-dns","name":"hickory-dns","platforms":[],"versions":[{"version":"0.26.0","status":"affected","lessThan":"0.26.2","versionType":"semver"},{"version":"0.26.2","status":"unaffected","versionType":"semver"}],"defaultStatus":"unaffected","packageURL":"pkg:cargo/hickory-resolver","packageIdentity":{"ecosystem":"crates.io","name":"hickory-resolver"},"cpes":[],"source":"VulnCheck","url":"https://www.cve.org/CVERecord?id=CVE-2026-123603"},{"vendor":"hickory-dns","name":"hickory-dns","platforms":[],"versions":[{"version":"0.26.0","status":"affected","lessThan":"0.26.2","versionType":"semver"},{"version":"0.26.2","status":"unaffected","versionType":"semver"}],"defaultStatus":"unaffected","packageURL":"pkg:cargo/hickory-proto","packageIdentity":{"ecosystem":"crates.io","name":"hickory-proto"},"cpes":[],"source":"VulnCheck","url":"https://www.cve.org/CVERecord?id=CVE-2026-123603"},{"vendor":"hickory-dns","name":"hickory-dns","platforms":[],"versions":[{"version":"0.25.0-alpha.1","status":"affected","lessThan":"0.26.2","versionType":"semver"},{"version":"0.26.2","status":"unaffected","versionType":"semver"}],"defaultStatus":"unaffected","packageURL":"pkg:cargo/hickory-server","packageIdentity":{"ecosystem":"crates.io","name":"hickory-server"},"cpes":[],"source":"VulnCheck","url":"https://www.cve.org/CVERecord?id=CVE-2026-123603"}],"remediation":[],"references":["https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-4jwp-xjwm-333g","https://www.vulncheck.com/advisories/hickory-dns-missing-ipv4-mapped-ipv6-canonicalization-access-control-bypass"],"sources":[{"name":"CVE","id":"CVE-2026-123603","modified":"2026-11-13T03:10:51.830Z","url":"https://www.cve.org/CVERecord?id=CVE-2026-123603"}],"assessments":[{"source":"VulnCheck","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","score":6.9},{"source":"VulnCheck","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","score":6.5}],"sourceAffected":[],"observedAt":"2026-11-13T07:16:29.568Z","kev":{"status":"not-listed","checkedAt":"2026-11-15T04:00:32.782Z"},"coverage":[{"source":"NVD","status":"no-result","checkedAt":"2026-11-08T02:05:40.186Z","attemptedAt":"2026-11-08T02:05:40.186Z"},{"source":"GHSA","status":"no-result","checkedAt":"2026-11-08T02:05:39.667Z","attemptedAt":"2026-11-08T02:05:39.667Z"},{"source":"EUVD","status":"refresh-failed","attemptedAt":"2026-11-08T02:05:37.598Z"},{"source":"EPSS","status":"no-result","checkedAt":"2026-11-08T02:05:38.878Z","attemptedAt":"2026-11-08T02:05:38.878Z"}],"evidence":[],"aiSummary":{"text":"Hickory DNS versions 0.26.0 before 0.26.2, 0.25.0-alpha.1 before 0.26.2, and 0.25.0-alpha.3 through 0.26.0-alpha.1 have an access control bypass weakness due to missing IPv4-mapped IPv6 canonicalization. Attackers may use IPv4-mapped addresses to evade filtering or reach denied servers.","model":"@cf/meta/llama-3.3-70b-instruct-fp8-fast","generatedAt":"2026-11-08T02:06:39.652Z","sources":[{"name":"CVE","url":"https://www.cve.org/CVERecord?id=CVE-2026-123603"}]}}