{"cve":"CVE-2026-39409","nvd":{"published":"2026-04-08T15:16:14.990","modified":"2026-07-24T21:10:00.143","status":"Analyzed","description":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.12, ipRestriction() does not canonicalize IPv4-mapped IPv6 client addresses (e.g. ::ffff:127.0.0.1) before applying IPv4 allow or deny rules. In environments such as Node.js dual-stack, this can cause IPv4 rules to fail to match, leading to unintended authorization behavior. This vulnerability is fixed in 4.12.12.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","score":6.3},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","score":5.3},"cwes":["CWE-180"],"references":["https://github.com/honojs/hono/commit/48fa2233bc092f650119f42df043050737cabf39","https://github.com/honojs/hono/releases/tag/v4.12.12","https://github.com/honojs/hono/security/advisories/GHSA-xpcf-pg52-r92g"],"products":["hono:hono"],"source":"nvd","synced_at":"2026-10-19T22:28:59.047572785+00:00"},"epss":{"cve":"CVE-2026-39409","score":0.00343,"percentile":0.27832,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-xpcf-pg52-r92g","url":"https://osv.dev/vulnerability/GHSA-xpcf-pg52-r92g","summary":"Hono has incorrect IP matching in ipRestriction() for IPv4-mapped IPv6 addresses","modified":"2026-09-10T03:50:44.898181069Z","packages":[{"ecosystem":"npm","name":"hono","purl":"pkg:npm/hono","ranges":["<4.12.12"],"fixed":["4.12.12"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}