Advisory Database
  • Advisories
  • Dependency Scanning
  1. npm
  2. ›
  3. h3
  4. ›
  5. GHSA-72gr-qfp7-vwhw

GHSA-72gr-qfp7-vwhw: h3: Double Decoding in `serveStatic` Bypasses `resolveDotSegments` Path Traversal Protection via `%252e%252e`

March 20, 2026

The serveStatic utility in h3 applies a redundant decodeURI() call to the request pathname after H3Event has already performed percent-decoding with %25 preservation. This double decoding converts %252e%252e into %2e%2e, which bypasses resolveDotSegments() (since it checks for literal . characters, not percent-encoded equivalents). When the resulting asset ID is resolved by URL-based backends (CDN, S3, object storage), %2e%2e is interpreted as .. per the URL Standard, enabling path traversal to read arbitrary files from the backend.

References

  • github.com/advisories/GHSA-72gr-qfp7-vwhw
  • github.com/h3js/h3
  • github.com/h3js/h3/security/advisories/GHSA-72gr-qfp7-vwhw

Code Behaviors & Features

Detect and mitigate GHSA-72gr-qfp7-vwhw with GitLab Dependency Scanning

Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →

Affected versions

All versions before 1.15.9

Fixed versions

  • 1.15.9

Solution

Upgrade to version 1.15.9 or above.

Impact 5.9 MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Learn more about CVSS

Weakness

  • CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Source file

npm/h3/GHSA-72gr-qfp7-vwhw.yml

Spotted a mistake? Edit the file on GitLab.

  • Site Repo
  • About GitLab
  • Terms
  • Privacy Statement
  • Contact

Page generated Tue, 24 Mar 2026 12:17:15 +0000.