Open Redirect in Vercel Next.js
CVE-2026-64645
Next.js is a React framework for building full-stack web applications. In versions 12.0.0 through 15.5.20 and 16.0.0 through 16.2.10, a rewrites() or redirects() rule that builds its external destination hostname from request-controlled input can be pointed at an arbitrary hostname, regardless of the rule's hostname suffix. For a rewrite, Next.js proxies the request to that arbitrary host and serves the response from the application's origin, leading to Server-Side Request forgery. A redirects() rule configured this way is vulnerable to an Open Redirect. This issue has been fixed in versions 15.5.21 and 16.2.11.
Vulnerability class: Open Redirect
EPSS: 0.009 (58.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
Affected products
- Vercel Next.js — versions >= 12.0.0 < 15.5.21, >= 16.0.0, < 16.2.11
Weakness classification (CWE)
References
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Product, x_refsource_MISC, Release Notes)
- security-advisories@github.com (Product, x_refsource_MISC, Release Notes)
- security-advisories@github.com (x_refsource_CONFIRM, Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-64645?
- CVE-2026-64645 is a medium-severity vulnerability in Vercel Next.js, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 6.1/10. Published 2026-07-27.
- How severe is CVE-2026-64645?
- Medium severity. CVSS v3 base score is 6.1 out of 10.