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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-40299 Detail

Description

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]`.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 6.9 MEDIUM
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/amannn/next-intl/commit/1c80b668aa6d853f470319eec10a3f61e78a70e6 GitHub, Inc.
https://github.com/amannn/next-intl/pull/2304 GitHub, Inc.
https://github.com/amannn/next-intl/releases/tag/v4.9.1 GitHub, Inc.
https://github.com/amannn/next-intl/security/advisories/GHSA-8f24-v5vv-gm5j GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-601 URL Redirection to Untrusted Site ('Open Redirect') GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-40299
NVD Published Date:
04/17/2026
NVD Last Modified:
04/17/2026
Source:
GitHub, Inc.