CVE-2026-40299
next-intl has an open redirect vulnerability
- State
- Published
- Severity
- 6.9 Medium
- Published
- Apr 17, 2026
- Updated
- Apr 20, 2026
- Reserved
- Apr 10, 2026
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 `next-intl@4.9.1`.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.9 Medium | 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 | GitHub_M |
Weaknesses
- CWE-601 URL Redirection to Untrusted Site ('Open Redirect')
Affected Products
| Product | Versions |
|---|---|
next-intlamannn |
|
References
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