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

Read the record on cve.org

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

CVSSScoreVectorSource
4.06.9 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:NGitHub_M

Weaknesses

  • CWE-601 URL Redirection to Untrusted Site ('Open Redirect')

Affected Products

ProductVersions
next-intlamannn
  • < 4.9.1Affected

References

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