In mintplex-labs/anything-llm, an attacker can exploit improper input validation by sending a malformed JSON payload to the '/system/enable-multi-user' endpoint. This triggers an error that is caught by a catch block, which in turn deletes all users and disables the 'multi_user_mode'. The vulnerability allows an attacker to remove all existing users and potentially create a new admin user without requiring a password, leading to unauthorized access and control over the application.

References

• https://nvd.nist.gov/vuln/detail/CVE-2024-3029
• Mintplex-Labs/anything-llm@99cfee1
• https://huntr.com/bounties/7189a7a0-9830-459d-b853-bdc2559999a0