VDB
KO
MEDIUM

GHSA-955p-x3mx-jcvp

Next.js: Unauthenticated disclosure of internal Server Function endpoints

Quick fix

GHSA-955p-x3mx-jcvp — next: upgrade to the fixed version with the command below.

npm install next@15.5.21

Details

## Impact

In Next.js applications using App Router, Server Actions (`use server`) or `use cache` endpoints can be disclosed bypassing any authentication on the pages where these endpoints are usually used.

Server Action IDs can be disclosed to unauthenticated users via publicly served client artifacts (for example, static chunks containing action references).

Affected users are applications using App Router + Server Actions.

By itself, this disclosure is typically a recon/enumeration primitive; however, it can increase risk when combined with other weaknesses. ## Workarounds

Never assume any authentication claims at the `use cache` or `use server` boundary. Always authenticate within the boundary.

Are you affected?

Enter the version of the package you're using.

Affected packages

npm / next
Introduced in: 13.0.0 Fixed in: 15.5.21
Fix npm install next@15.5.21
npm / next
Introduced in: 16.0.0 Fixed in: 16.2.11
Fix npm install next@16.2.11

References