GHSA-v853-p72q-4cfw: Quart Quart Leaks Raw Request Body Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-v853-p72q-4cfw",
  "modified" : "2026-10-05T22:49:44Z",
  "published" : "2026-10-05T22:49:44Z",
  "aliases" : [ ],
  "summary" : "Quart leaks raw request body (incl. plaintext passwords) to stdout via stray debug print in Body.__await__",
  "details" : "### Summary\nQuart 0.23.0 contains a stray debug statement (`print(data)`) inside `Body.__await__` in `quart/wrappers/request.py`. Any request whose body is awaited — `await request.form`, `await request.get_data()`, WTForms `validate_on_submit()`, etc. — has its raw, unparsed body printed to stdout, including plaintext form fields such as passwords and CSRF tokens. Confirmed present in 0.23.0, confirmed absent in 0.22.0.\n\n### Details\nIn `src/quart/wrappers/request.py`, `Body.__await__` accumulates the request body into a bytearray:\n\n​```python\ndata = bytearray()\nwhile not self._queue.empty():\n    data.extend(self._queue.get_nowait())\n    print(data)          # <-- not present in 0.22.0\n    if (\n        self._max_content_length is not None\n        and len(data) > self._max_content_length\n    ):\n        raise RequestEntityTooLarge()\n​```\n\nThis fires for every request that awaits its body — the overwhelming majority of POST/PUT routes in a typical Quart app (form submissions, JSON APIs via `request.get_json()`, file uploads, etc.).\n\n### PoC\n1. `pip install quart==0.23.0` (requires Python 3.13+)\n2. Minimal route:\n​```python\n@app.route(\"/login\", methods=[\"POST\"])\nasync def login():\n    form_data = await request.form\n    ...\n​```\n3. Submit a POST with form data, e.g. a login form with `staff_id`/`password` fields.\n4. Observe stdout: the full raw body is printed as `bytearray(b'csrf_token=...&staff_id=...&password=...')`.\n\nConfirmed via source diff against 0.22.0's `request.py`, where this line does not exist.\n\n### Impact\nAny app that captures stdout in logs (terminal redirect, systemd/journald, Docker logs, cloud log aggregation, etc.) will have every submitted form body — including login credentials — written to logs in plaintext. This affects any Quart 0.23.0 app handling authentication or any sensitive form data, and is trivially triggerable by any user simply submitting a form (no attacker action required beyond normal use).",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "quart"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.23.0"
      }, {
        "fixed" : "0.23.1"
      } ]
    } ],
    "versions" : [ "0.23.0" ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/pallets/quart/security/advisories/GHSA-v853-p72q-4cfw"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pallets/quart/commit/e8eb3b8a0cb98e7574bf3841312fc7f96883d055"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/pallets/quart"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pallets/quart/releases/tag/0.23.1"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-532" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-10-05T22:49:44Z",
    "nvd_published_at" : null
  }
}