CVE-2026-41691

Technical Description

Copilot said: i18nextify is a JavaScript library that adds

i18nextify is a JavaScript library that adds website internationalization via a script tag, without source code changes. Versions prior to 3.0.5 interpolate the lng and ns values directly into the configured loadPath / addPath URL template without any encoding, validation, or path sanitisation. When an application exposes the language-code selection to user-controlled input (the default — i18next-browser-languagedetector reads ?lng= query params, cookies, localStorage, and request headers), an attacker can inject characters that change the structure of the outgoing request URL. This is a single URL-injection vulnerability. The attacker-controlled value is neutralised before it is used as part of an output URL string; the attack shape covers both path traversal and broader URL-structure injection — both are closed by the one interpolateUrl sanitisation fix. This issue has been fixed in version 3.0.5. If users cannot upgrade imme

Remediation

Check the references section for vendor advisories and patches from i18next. Update i18next-http-backend to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

Affected Products

References