Executive brief
Langchain-Chatchat, an application for building local knowledge bases with large language models, contains a security flaw in its file management service. This vulnerability allows unauthorized users on the same local network to list, read, or delete files without providing any credentials. This could lead to the exposure of sensitive documents or the disruption of the application's knowledge base.
Technical details
A missing authentication vulnerability (CWE-306) exists in Langchain-Chatchat versions up to 0.3.1.3 within the 'Compatible File Service' component. The flaw is located in the 'openai_routes.py' file, specifically affecting the 'files/list_files', 'retrieve_file', 'retrieve_file_content', and 'delete_file' functions. An attacker with local network access can interact with these endpoints without authentication to list, download, or delete files stored within the application. While the project was notified via an issue report, no official patch has been confirmed at the time of this advisory.
Affected products
- chatchat-space Langchain-Chatchat up to 0.3.1.3
Timeline
- 2026-04-13: disclosed: Issue reported to the project maintainers via GitHub issue #5465
- 2026-05-05: advisory: Vulnerability published in NVD and VulDB
References
- https://github.com/3em0/cve_repo/blob/main/Langchain-Chatchat/Vuln-4-Missing-Auth-File-Endpoints.md
- https://github.com/chatchat-space/Langchain-Chatchat/
- https://github.com/chatchat-space/Langchain-Chatchat/issues/5465
- https://vuldb.com/submit/807790
- https://vuldb.com/vuln/361123
- https://vuldb.com/vuln/361123/cti