CVE-2026-64646
Medium
Description
Next.js is a React framework for building full-stack web applications. In versions 13.0.0 through 15.5.20 and 16.0.0 through 16.2.10, requests targeting Next.js applications using App Router with at least one Server Action can lead to excessive memory consumption if that Server Actions uses the Edge runtime. This issue has been fixed in versions 15.5.21 and 16.2.11.
SeverityMedium
CVSS5.3
Exploit probability—
Product
Vercel Next.js
PublishedJul 27, 2026
First seenJul 27, 2026
Weakness typeCWE-770Allocation of resources without limits
How to fix
Update
- vercel next.js15.5.21, 16.2.11 or later
- next15.5.21, 16.2.11 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| vercel next.js | 13.0.0 ≤ v < 15.5.21, 16.0.0 ≤ v < 16.2.11 | 15.5.21, 16.2.11 |
| nextnpm | 13.0.0 ≤ v < 15.5.21, 16.0.0 ≤ v < 16.2.11 | 15.5.21, 16.2.11 |
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