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: 6.9 [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]
CVE-ID: CVE-2026-64646
CWE-ID: CWE-770
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
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.
Affected software
Next.js
How to mitigate CVE-2026-64646
Install security update from vendor's website.
Next.js - addressed in versions 15.5.21, 16.2.11