{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "1.15.6"
              },
              {
                "introduced": "2.0.0-beta.0"
              },
              {
                "fixed": "2.0.1-rc.15"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "829daf157e5add61d60fb18dfdd9f6885e57a5e3"
            },
            {
              "introduced": "8120545c3ce65f0149f59d72d4db7cb1a53b83e3"
            },
            {
              "fixed": "91361835657410605f2041762da9e3f60d24ecfb"
            }
          ],
          "repo": "https://github.com/h3js/h3",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-wr4h-v87w-p3r7"
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-22"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86253.json"
  },
  "details": "h3 (npm package) versions \u003c= 2.0.1-rc.14 contain a path traversal vulnerability in serveStatic(). On Node.js deployments, event.url.pathname is not normalized, so percent-encoded dot segments (%2e%2e) are passed to decodeURI() and decoded to ../ sequences without sanitization. An unauthenticated remote attacker can send crafted requests to endpoints served by serveStatic() to read arbitrary files outside the intended static directory. Fixed in 1.15.6 and 2.0.1-rc.15.",
  "id": "CVE-2026-86253",
  "modified": "2026-09-12T03:31:01.522148932Z",
  "published": "2026-09-06T12:00:28.232Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86253.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/h3js/h3/security/advisories/GHSA-wr4h-v87w-p3r7"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-86253"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/h3-before-1.15.6-path-traversal-via-percent-encoded-dot-segments"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "h3 before 1.15.6 Path Traversal via Percent-Encoded Dot Segments"
}