In BASETech GE-131 BT-1837836 firmware 20180921, the web-server on the system is configured with the option “DocumentRoot /etc“. This allows an attacker with network access to the web-server to download any files from the “/etc” folder without authentication. No path traversal sequences are needed to exploit this vulnerability.
https://infosec.rm-it.de/2020/11/04/basetech-ip-camera-analysis/#vulns