A pre-authentication stack-based buffer overflow vulnerability exists in the http_gdpr_decrypt function of TL-MR100 V3.20 due to insufficient bounds checking of encrypted requests to the /cgi/login endpoint. An adjacent unauthenticated attacker with access to the router's web management interface can trigger memory corruption and potentially achieve arbitrary code execution. Successful exploitation can overwrite saved control-flow data on the httpd process stack prior to authentication, resulting in a service crash or potential arbitrary code execution in the context of the affected process.