{"id":"CVE-2026-86253","title":"h3 (npm package) versions <= 2.0.1-rc.14 contain a path traversal vulnerability in serveStatic()","summary":"h3 (npm package) versions <= 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 decode…","severity":"medium","cvss":5.9,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","cwe":["CWE-22"],"vendor":"h3js","product":"h3","affected":["h3 < 1.15.6","h3 >= 2.0.0-beta.0 < 2.0.1-rc.15"],"published":"2026-09-06","updated":"2026-09-10","sourceUpdated":"2026-09-10T16:18:02.287","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-86253","references":[{"url":"https://github.com/h3js/h3/security/advisories/GHSA-wr4h-v87w-p3r7","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/h3-before-1.15.6-path-traversal-via-percent-encoded-dot-segments","label":"disclosure@vulncheck.com"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-86253.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-86253"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2529156"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-86253"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86253"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-10T14:19:05.242837Z"},"epss":0.00429,"epssPercentile":0.36773,"ingestedAt":"2026-09-07T04:04:50.629Z","slug":"CVE-2026-86253","body":"## Overview\n\nh3 (npm package) versions <= 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat OpenShift AI (RHOAI) · no fix planned: Red Hat OpenShift AI (RHOAI) · updated 2026-09-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-86253.json)","depth":"sunlit","depthScore":33,"depthScoreParts":{"impact":32.5,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}