CVE-2026-64643
Severity CVSS v4.0:
MEDIUM
Type:
Unavailable / Other
Publication date:
27/07/2026
Last modified:
29/07/2026
Description
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, Next.js applications using App Router, Server Actions (use server) or use cache endpoints can be disclosed bypassing any authentication on the pages where these endpoints are usually used. Server Action IDs can be disclosed to unauthenticated users via publicly served client artifacts (for example, static chunks containing action references). Affected users are applications using App Router and Server Actions. By itself, this disclosure is typically a recon/enumeration primitive; however, it can increase risk when combined with other weaknesses. This issue has been fixed in versions 15.5.21 and 16.2.11.
Impact
Base Score 4.0
6.30
Severity 4.0
MEDIUM
Base Score 3.x
5.30
Severity 3.x
MEDIUM
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:* | 13.0.0 (including) | 15.5.21 (excluding) |
| cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:* | 16.0.0 (including) | 16.2.11 (excluding) |
To consult the complete list of CPE names with products and versions, see this page
References to Advisories, Solutions, and Tools
- https://github.com/vercel/next.js/commit/1b0c3ae912a3ad925c60065cc8d55b070fa8bcd3
- https://github.com/vercel/next.js/commit/ff12a6124e1504f17b62de948b8a553fdecaef7b
- https://github.com/vercel/next.js/releases/tag/v15.5.21
- https://github.com/vercel/next.js/releases/tag/v16.2.11
- https://github.com/vercel/next.js/security/advisories/GHSA-955p-x3mx-jcvp