CVE-2026-33497: langflow /profile_pictures/{folder_name}/{file_name} Endpoint File Reading Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-ph9w-r52h-28p7",
  "modified" : "2026-06-06T00:56:31Z",
  "published" : "2026-03-20T20:56:14Z",
  "aliases" : [ "CVE-2026-33497" ],
  "summary" : "langflow: /profile_pictures/{folder_name}/{file_name} endpoint file reading",
  "details" : "## Vulnerability\n\n### Path Traversal in `GET /api/v1/files/profile_pictures/{folder_name}/{file_name}`\n\nThe `download_profile_picture` function in `src/backend/base/langflow/api/v1/files.py` constructed file paths by directly concatenating the user-supplied `folder_name` and `file_name` path parameters without sanitization or boundary validation. The resulting path was passed to the filesystem without verifying it remained within the intended directory.\n\nAn unauthenticated attacker could supply traversal sequences (e.g. `../secret_key`) to navigate outside the profile pictures directory and read arbitrary files on the server filesystem.\n\nThis exposed the server to:\n\n- **Sensitive file disclosure** — any file readable by the application process could be retrieved\n- **Secret key exfiltration** — the application's `secret_key` file, used as JWT signing material, could be read directly via `../secret_key`\n- **Authentication bypass** — with the `secret_key` in hand, an attacker can forge valid JWT tokens and authenticate as any user, including administrators\n\n---\n\n## Proof of Concept\n\n```bash\ncurl --path-as-is 'http://<host>:7860/api/v1/files/profile_pictures/../secret_key'\n```\n\nA successful response returns the raw secret key value used to sign all JWT authentication tokens in the instance.\n\n---\n\n## Fix\n\nThe fix was applied in `src/backend/base/langflow/api/v1/files.py` (PR #12263).\n\nTwo layers of defense were introduced:\n\n**1. Typed path validation** — the `folder_name` and `file_name` parameters were changed from plain `str` to `ValidatedFolderName` and `ValidatedFileName` annotated types that reject traversal characters at the FastAPI input layer.\n\n**2. Path containment check** — `Path.name` is used to strip any directory component from the inputs before path construction, and `Path.is_relative_to()` verifies the resolved path remains within the allowed base directory. This replaces the previous `startswith()` check, which was susceptible to prefix-ambiguity bugs.\n\n```diff\n @router.get(\"/profile_pictures/{folder_name}/{file_name}\")\n async def download_profile_picture(\n-    folder_name: str,\n-    file_name: str,\n+    folder_name: ValidatedFolderName,\n+    file_name: ValidatedFileName,\n     settings_service: Annotated[SettingsService, Depends(get_settings_service)],\n ):\n```\n\n```diff\n-        file_path = (config_path / \"profile_pictures\" / folder_name / file_name).resolve()\n+        safe_folder = Path(folder_name).name\n+        safe_file = Path(file_name).name\n+        file_path = (config_path / \"profile_pictures\" / safe_folder / safe_file).resolve()\n\n         allowed_base = (config_path / \"profile_pictures\").resolve()\n-        if not str(file_path).startswith(str(allowed_base)):\n-            raise HTTPException(status_code=404, detail=\"Profile picture not found\")\n+        if not file_path.is_relative_to(allowed_base):\n+            raise HTTPException(status_code=404, detail=\"Profile picture not found\")\n```\n\n---\n\n## Workarounds\n\nIf you cannot upgrade immediately, restrict network access to the `/api/v1/files/profile_pictures/` endpoint at the reverse-proxy or firewall level. Rotating the `secret_key` is strongly recommended if exposure cannot be ruled out.\n\n---\n\n## Acknowledgements\n\nWe thank the security researcher who responsibly disclosed this vulnerability.\n\n- [r00tuser111](https://github.com/r00tuser111)",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "langflow"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.7.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/langflow-ai/langflow/security/advisories/GHSA-ph9w-r52h-28p7"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-33497"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/langflow-ai/langflow"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/langflow/PYSEC-2026-81.yaml"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-22" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-20T20:56:14Z",
    "nvd_published_at" : "2026-03-24T14:16:30Z"
  }
}