CVE-2026-64646

Next.js: Unbounded Server Action payload in Edge runtime

Published: Jul 27, 2026Updated: Jul 29, 2026 Sources: CVE List NVDCWE-770

5.3MEDIUM

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:LAvailability

Low

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Weaknesses

CWE-770

Affected Products

vercel

commercial·US

next.jsLibraryLibrary

OSS Libraries / web-framework

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Impact

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References

https://github.com/vercel/next.js/commit/57c31f724d746e86a9e8b92aa8be538a922446a4

github.com

https://github.com/vercel/next.js/commit/9a4651e754f70b12e397694ffc41f44c3ba8cc17

github.com

https://github.com/vercel/next.js/releases/tag/v15.5.21

github.com

and 2 more references View all →

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