GHSA-mg66-mrh9-m8jx

### Impact

Applications using Partial Prerendering through the Cache Components feature can be vulnerable to connection exhaustion through crafted POST requests to a server action. In affected configurations, a malicious request can trigger a request-body handling deadlock that leaves connections open for an extended period, consuming file descriptors and server capacity until legitimate users are denied service.

### Fix

We now treat the header used for resuming Partial Prerendered requests as an internal-only header and strip it from untrusted incoming requests. This header should never be accepted directly from external clients.

### Workarounds

If you cannot upgrade immediately, block requests that would be handled by Next.js if they contain the `Next-Resume` header at the edge.