vulnerability / NVI-00018322 / Revision 1
Langflow: Unauthenticated file upload leads to DoS (space exhaustion) and information leak
GitHub lists this reviewed advisory for langflow. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
9.3 critical
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
langflow
source listed< 1.9.1
### Summary Unauthenticated users can upload any amount of data to the server without any limitations. No need for any prior knowledge, only network access to Langflow. This can lead to space exhaustion on the server. In adition, in the response, the absolute path of the uploaded file is reported to the attacker, which is an information leak that can assist in chaining other primitives. Tested on commit 2d67402b1dbaefcbce85a244d4a6cd5e4bda1cfe ### Details Code is in `langflow/api/v1/endpoints.py`: ```python @router.post( "/upload/{flow_id}", status_code=HTTPStatus.CREATED, deprecated=True, ) async def create_upload_file( file: UploadFile, flow_id: UUID, ) -> UploadFileResponse: ... ``` As can be seen above, there is no authentication. There is not validation over `flow_id` as well, unlike other endpoints: ``` flow_id_str = str(flow_id) file_path = await asyncio.to_thread(save_uploaded_file, file, folder_name=flow_id_str) ``` Function `save_uploaded_file` saves the file to local file-system. Suggested fix: 1. Add authentication to route. 2. Only return relative path or filename. ### PoC PoC: ```bash curl 'http://localh
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-x223-p2gf-v735 ↗
GitHub Advisory Database · vendor advisory
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Public revision history
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- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.