{"id":"CVE-2026-40299","summary":"next-intl has an open redirect vulnerability","details":"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`.","aliases":["GHSA-8f24-v5vv-gm5j"],"modified":"2026-07-15T01:49:14.611595882Z","published":"2026-04-17T20:49:05.642Z","database_specific":{"cwe_ids":["CWE-601"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40299.json","cna_assigner":"GitHub_M"},"references":[{"type":"WEB","url":"https://github.com/amannn/next-intl/releases/tag/v4.9.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40299.json"},{"type":"ADVISORY","url":"https://github.com/amannn/next-intl/security/advisories/GHSA-8f24-v5vv-gm5j"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-40299"},{"type":"FIX","url":"https://github.com/amannn/next-intl/commit/1c80b668aa6d853f470319eec10a3f61e78a70e6"},{"type":"FIX","url":"https://github.com/amannn/next-intl/pull/2304"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/amannn/next-intl","events":[{"introduced":"0"},{"fixed":"1c80b668aa6d853f470319eec10a3f61e78a70e6"},{"fixed":"b4aa5380c50ad59a80d1dfdbc229590a4e0133a3"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"4.9.1"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["v4.9.0","v4.8.4","v4.8.3","v4.8.2","v4.8.1","v4.8.0","v4.7.0","v4.6.1","v4.6.0","v4.5.8","v4.5.7","v4.5.6","v4.5.5","v4.5.4","v4.5.3","v4.5.2","v4.5.1","v4.5.0","v4.4.0","v4.3.12","v4.3.11","v4.3.10","v4.3.9","v4.3.8","v4.3.7","v4.3.6","v4.3.5","v4.3.4","v4.3.3","v4.3.2","v4.3.1","v4.3.0","v4.2.0","v4.1.0","v4.0.3","v4.0.2","v4.0.1","v4.0.0","v3.26.5","v3.26.4","v3.26.3","v3.26.2","v3.26.1","v3.26.0","v3.25.3","v3.25.2","v3.25.1","v3.25.0","v3.24.0","v3.23.5","v3.23.4","v3.23.3","v3.23.2","v3.23.1","v3.23.0","v3.22.0","v3.21.1","v3.21.0","v3.20.0","v3.19.5","v3.19.4","v3.19.3","v3.19.2","v3.19.1","v3.19.0","v3.18.1","v3.18.0","v3.17.6","v3.17.5","v3.17.4","v3.17.3","v3.17.2","v3.17.1","v3.17.0","v3.16.0","v3.15.5","v3.15.4","v3.15.3","v3.15.2","v3.15.1","v3.15.1-canary.1","v3.16.0-canary.4","v3.16.0-canary.3","v3.16.0-canary.2","v3.16.0-canary.1","v3.16.0-canary.0","v3.15.1-canary.0","v3.15.0","v3.14.1","v3.14.0","v3.13.0","v3.12.2","v3.12.1","v3.12.0","v3.11.3","v3.11.2","v3.11.1","v3.11.0","v3.10.0","v3.9.5","v3.9.4","v3.9.3","v3.9.2","v3.9.1","v3.9.0","v3.8.0","v3.7.0","v3.6.0","v3.5.4","v3.5.3","v3.5.2","v3.5.1","v3.5.0","v3.4.5","v3.4.4","v3.4.3","v3.4.2","v3.4.1","v3.4.0","v3.3.3","v3.3.2","v3.3.1","v3.3.0","v3.2.5","v3.2.4","v3.2.3","v3.2.2","v3.2.1","v3.2.0","v3.1.4","v3.1.3","v3.1.2","v3.1.1","v3.1.0","v3.0.3","v3.0.2","v3.0.1","v2.22.1","v2.22.0","v2.21.0","v2.20.2","v2.20.1","v2.20.0","v2.19.4","v2.19.3","v2.19.2","v2.19.1","v2.19.0","v2.18.0","v2.17.5","v2.17.4","v2.17.3","v2.17.2","v2.17.1","v2.17.0","v2.16.0","v2.15.1","v2.15.0","v2.14.6","v2.14.5","v2.14.4","v2.14.3","v2.14.2","v2.14.1","v2.14.0","v2.13.4","v2.13.3","v2.13.2","v2.13.1","v2.13.0","v2.12.0","v2.11.0","v2.10.4","v2.10.3","v2.10.2","v2.10.1","v2.10.0","v2.9.2","v2.9.1","v2.9.0","v2.8.0","v2.7.6","v2.7.5","v2.7.4","v2.7.3","v2.7.2","v2.7.1","v2.7.0","v2.6.0","v2.3.5","v2.3.4","v2.3.3","v2.3.2","v2.3.1","v2.3.0","v2.2.1","v2.2.0","v2.1.1","v2.1.0","v2.0.5","v2.0.4","v2.0.3","v2.0.2","v2.0.1","v2.0.0","v1.5.1","v1.5.0","v1.4.7","v1.4.6","v1.4.5","v1.4.4","v1.4.1","v1.4.0","v1.3.11","v1.3.10","v1.3.8","v1.3.7","v1.3.6","v1.3.2","v0.1.0","v0.0.5","v0.0.4","v0.0.3"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-40299.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"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"}]}