CVE-2026-40299

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 `next-intl@4.9.1`.

CVSS

No CVSS.

References

Link	Resource
https://github.com/amannn/next-intl/commit/1c80b668aa6d853f470319eec10a3f61e78a70e6
https://github.com/amannn/next-intl/pull/2304
https://github.com/amannn/next-intl/releases/tag/v4.9.1
https://github.com/amannn/next-intl/security/advisories/GHSA-8f24-v5vv-gm5j

Configurations

No configuration.

History

17 Apr 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-17 21:16

Updated : 2026-04-29 21:04

NVD link : CVE-2026-40299

Mitre link : CVE-2026-40299

CVE.ORG link : CVE-2026-40299

JSON object : View

Products Affected

No product.

CWE

CWE-601

URL Redirection to Untrusted Site ('Open Redirect')

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