CVE-2025-59472

A denial of service vulnerability exists in Next.js versions with Partial Prerendering (PPR) enabled when running in minimal mode. The PPR resume endpoint accepts unauthenticated POST requests with the Next-Resume: 1 header and processes attacker-controlled postponed state data. Two closely related vulnerabilities allow an attacker to crash the server process through memory exhaustion:

1. Unbounded request body buffering: The server buffers the entire POST request body into memory using Buffer.concat() without enforcing any size limit, allowing arbitrarily large payloads to exhaust available memory.

2. Unbounded decompression (zipbomb): The resume data cache is decompressed using inflateSync() without limiting the decompressed output size. A small compressed payload can expand to hundreds of megabytes or gigabytes, causing memory exhaustion.

Both attack vectors result in a fatal V8 out-of-memory error (`FATAL ERROR: Reached heap limit Allocation failed - JavaScript hea