Allocation of Resources Without Limits or Throttling in Next.js - CVE-2026-64646
Published: July 22, 2026
Vulnerability identifier: #VU139029
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-64646
CWE-ID: CWE-770
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: vercel
Affected software:
Next.js
Next.js
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to allocation of resources without limits or throttling in Server Actions using the Edge runtime when handling requests targeting App Router applications. A remote attacker can send a large request payload to cause a denial of service.
Only Next.js applications using App Router with at least one Server Action that uses the Edge runtime are vulnerable.
How to mitigate CVE-2026-64646
Install security update from vendor's website.