CVE-2026-64648
Received
Received - Intake
Next.js Cache Leak in Fetch Requests
Vulnerability report for CVE-2026-64648, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-07-27
Last updated on: 2026-07-27
Assigner: GitHub, Inc.
Description
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.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| vercel | next.js | From 12.0.0 (inc) to 15.5.20 (inc) |
| vercel | next.js | From 16.0.0 (inc) to 16.2.10 (inc) |
| vercel | next.js | 15.5.21 |
| vercel | next.js | 16.2.11 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-524 | The code uses a cache that contains sensitive information, but the cache can be read by an actor outside of the intended control sphere. |
