CVE-2026-64641

Next.js: Denial of Service in App Router using Server Actions

Published: Jul 22, 2026Modified: Jul 23, 2026

Severity

HIGH

CVSS Scores

0.0/ 10.0

CVSS_V4

Low

Vector String

CVSS:4.0/AV:N/AC:L/PR:N/UI:N

Details

Impact

Crafted requests targeting Next.js applications using App Router with at least one Server Action can lead to excessive CPU usage blocking processing of further requests in the same process.

Workarounds

No workaround exists besides upgrading. Applications using Pages Router or not using Server Actions are not vulnerable.

Affected Packages

nextnpm

Version Ranges:

Version Range: 13.0.0 - 15.5.21

nextnpm

Version Ranges:

Version Range: 16.0.0 - 16.2.11

References

https://github.com/vercel/next.js/security/advisories/GHSA-m99w-x7hq-7vfjWEB https://github.com/vercel/next.js/pull/96013WEB

Aliases

CVE-2026-64641

CVE-2026-64641 - Next.js: Denial of Service in App Router using Server Actions | OSV Watch