Security Bulletin: Multiple vulnerabilities in i18next-http-middleware affect IBM Cloud Pak System

Vulnerability Details

CVEID:   CVE-2026-41683
DESCRIPTION:   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 wrote user-controlled language values into the Content-Language response header after passing them through utils.escape(), which is an HTML-entity encoder that does not strip carriage return, line feed, or other control characters. When the application used an older i18next ( 19.5.0) that still exercised the backward-compatibility fallback at LanguageDetector.js:100 or otherwise produced a raw detected value, CRLF sequences in the attacker-controlled lng parameter reached res.setHeader('Content-Language', ...) verbatim. This issue has been patched in version 3.9.3.
CWE:   CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVSS Source:   security-advisories@github.com
CVSS Base score:   8.6
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L)

CVEID:   CVE-2026-41690
DESCRIPTION:   18next-http-middleware is a middleware to be used with Node.js web frameworks like express or Fastify and also for Deno. Versions prior to 3.9.3 allow an unauthenticated HTTP client to pollute Object.prototype in the Node.js process hosting the middleware, via two unvalidated entry points that reach internal object-key writes: getResourcesHandler and missingKeyHandler. This can break authorisation checks (if (user.isAdmin) returning true for any user), cause type-confusion DoS, and depending on downstream code it can be chained into RCE.
CWE:   CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CVSS Source:   security-advisories@github.com
CVSS Base score:   8.6
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L)

CVEID:   CVE-2026-42353
DESCRIPTION:   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.
CWE:   CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CVSS Source:   security-advisories@github.com
CVSS Base score:   8.2
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N)