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 server-side fetch with a request body may return a cached response body from a different request to the same URL but different body. Confidential data in the POST's response body would then leak to unauthorized requests. Though the request itself will not be deduped. This is only an issue when receiving request bodies with a content type charset other than UTF-8. For example, the UTF-16 byte sequences for 삃삃 and 섄섄 in the request body would share the same cache. This issue has been fixed in versions 15.5.21 and 16.2.11.
References
| Link | Resource |
|---|---|
| https://github.com/vercel/next.js/commit/025bf4a5f7b47fb7758c4ebf1c931a61c451c082 | Patch |
| https://github.com/vercel/next.js/pull/96008 | Issue Tracking Patch |
| https://github.com/vercel/next.js/releases/tag/v15.5.21 | Product Release Notes |
| https://github.com/vercel/next.js/releases/tag/v16.2.11 | Product Release Notes |
| https://github.com/vercel/next.js/security/advisories/GHSA-4633-3j49-mh5q | Vendor Advisory |
Configurations
Configuration 1 (hide)
|
History
29 Jul 2026, 14:38
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:* | |
| First Time |
Vercel
Vercel next.js |
|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 5.4 |
| References | () https://github.com/vercel/next.js/commit/025bf4a5f7b47fb7758c4ebf1c931a61c451c082 - Patch | |
| References | () https://github.com/vercel/next.js/pull/96008 - Issue Tracking, Patch | |
| References | () https://github.com/vercel/next.js/releases/tag/v15.5.21 - Product, Release Notes | |
| References | () https://github.com/vercel/next.js/releases/tag/v16.2.11 - Product, Release Notes | |
| References | () https://github.com/vercel/next.js/security/advisories/GHSA-4633-3j49-mh5q - Vendor Advisory |
27 Jul 2026, 19:17
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-07-27 19:17
Updated : 2026-07-29 14:38
NVD link : CVE-2026-64647
Mitre link : CVE-2026-64647
CVE.ORG link : CVE-2026-64647
JSON object : View
Products Affected
vercel
- next.js
CWE
CWE-116
Improper Encoding or Escaping of Output
