CVE-2026-42353 HIGH

CVE-2026-42353: Path traversal / SSRF in i18next-http-middleware via user-controlled language and namespace parameters

Vendor I18Next
Product i18next-http-middleware
Weakness CWE-22 · Path traversal
Published May 8, 2026
Last update May 8, 2026
View on NVD All CVEs

CVSS base score

8.2/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality High
Integrity Low

CVSS vector

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

What the vulnerability does

01Description

i18next-http-middleware is a middleware to be used with Node.js web frameworks like express or Fastify and also for Deno. Prior to version 3.9.3, i18next-http-middleware passes the user-controlled lng and ns values from getResourcesHandler directly into i18next.services.backendConnector.load(languages, namespaces, …) without any sanitization. Depending on which backend is configured, the unvalidated path segments enable either path traversal or SSRF. This issue has been patched in version 3.9.3.

Key dates

02Disclosure timeline

May 8, 2026 CVE published
May 8, 2026 Record updated