Summary

If an attacker can successfully authenticate through SSO/Access Code, they can obtain the real backend API Key by modifying the base URL to their own attack URL on the frontend and setting up a server-side request.

Details

The attack process is described above.

PoC

Frontend:

1. Pass basic authentication (SSO/Access Code).
2. Set the Base URL to a private attack address.
3. Configure the request method to be a server-side request.
4. At the self-set attack address, retrieve the API Key information from the request headers.

Backend:

1. The LobeChat version allows setting the Base URL.
2. There is no outbound traffic whitelist.

Impact

All community version LobeChat users using SSO/Access Code authentication, tested on version 0.162.13.

References

• GHSA-p36r-qxgx-jq2v
• https://nvd.nist.gov/vuln/detail/CVE-2024-37895