MediumGHSA-4c39-4ccg-62r3CVE-2026-64646

Next.js: Unbounded Server Action payload in Edge runtime

Published 22 Jul 2026 · Updated 10 Sept 2026

Affected packages

nextnpm

Affected: >=13.0.0 <15.5.21
Fixed in: 15.5.21

Update to the fixed version for your release line, for example:npm install next@15.5.21

nextnpm

Affected: >=16.0.0 <16.2.11
Fixed in: 16.2.11

Update to the fixed version for your release line, for example:npm install next@16.2.11

Details

Impact

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

Workarounds

If you cannot upgrade, ensure your hosting provider limits the request's body size. 5 MiB should be allowed at max by your hosting provider.

Is GHSA-4c39-4ccg-62r3 in any of your client repos?

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References

Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.