{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "cpe": "cpe:2.3:a:hono:hono:*:*:*:*:*:node.js:*:*",
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "last_affected": "4.12.11"
              }
            ],
            "source": [
              "CPE_RANGE",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "48fa2233bc092f650119f42df043050737cabf39"
            },
            {
              "fixed": "c37ba26da9709ad03b803d1972773ed864b7e60d"
            }
          ],
          "repo": "https://github.com/honojs/hono",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-xpcf-pg52-r92g"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-180"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39409.json"
  },
  "details": "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.",
  "id": "CVE-2026-39409",
  "modified": "2026-07-08T05:37:18.310509627Z",
  "published": "2026-04-08T14:43:36.476Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/honojs/hono/releases/tag/v4.12.12"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39409.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/honojs/hono/security/advisories/GHSA-xpcf-pg52-r92g"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39409"
    },
    {
      "type": "FIX",
      "url": "https://github.com/honojs/hono/commit/48fa2233bc092f650119f42df043050737cabf39"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Hono has incorrect IP matching in ipRestriction() for IPv4-mapped IPv6 addresses"
}