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CVE-2026-40299

CVE-2026-40299 · next-intl has an open redirect vulnerability

This page contains facts from public vulnerability sources. Check the original advisory before updating.

next-intl provides internationalization for Next.js. Applications using the `next-intl` middleware prior to version 4.9.1with `localePrefix: 'as-needed'` could construct URLs where path handling and the WHATWG URL parser resolved a relative redirect target to another host (e.g. scheme-relative `//` or control characters stripped by the URL parser), so the middleware could redirect the browser off-site while the user still started from a trusted app URL. The problem has been patchedin `[email protected]`.

CVSS 6.9 · Medium · EPSS 0.3% · Fix available

Published
Updated

Stack: node

Affected products and versions

  • next-intl

    Versions
    • < 4.9.1: Affected

    No fix published

  • next-intl npm

    Affected ranges
    • SEMVER: < 4.9.1

    Update to 4.9.1

Original sources

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