CVE-2026-40299 (GCVE-0-2026-40299)

Vulnerability from cvelistv5 – Published: 2026-04-17 20:49 – Updated: 2026-04-20 15:58
VLAI
Title
next-intl has an open redirect vulnerability
Summary
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`.
Severity
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
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-20 15:56 UTC
CWE
  • CWE-601 - URL Redirection to Untrusted Site ('Open Redirect')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7761 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
amannn next-intl Affected: < 4.9.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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