CVE-2026-64648
Severity CVSS v4.0:
MEDIUM
Type:
Unavailable / Other
Publication date:
27/07/2026
Last modified:
27/07/2026
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, 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 only applies to fetch calls with a request that has a different init than the one passed to fetch. A safe request would be: fetch(new Request(init), init). An unsafe request would be: fetch(new Request(init), aDifferentInit). This issue has been fixed in versions 15.5.21 and 16.2.11.
Impact
Base Score 4.0
6.00
Severity 4.0
MEDIUM
References to Advisories, Solutions, and Tools
- https://github.com/vercel/next.js/commit/062f66700b52a5d6bba2c0605d55577ab7ad262c
- https://github.com/vercel/next.js/commit/73b94872bc343d09494b50394d8c08eb9fc8e56a
- 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-68g3-v927-f742