This detection rule identifies suspicious activity in web applications by monitoring POST requests that receive a 403 Forbidden response. Such responses indicate that the requested action is not permitted, potentially revealing attempt(s) to exploit vulnerabilities, unauthorized access attempts, or malicious probing. The detection is based on specific query conditions that filter for HTTP POST requests with a response status code of 403. The rule serves as an alert mechanism for security teams to investigate these events, ensuring they can distinguish between legitimate application errors and suspicious behavior that may indicate a targeted attack. The inclusion of detailed triage steps and false positive analysis aids security personnel in efficiently assessing the alerts and determining the necessity for further action. The rule emphasizes the importance of reviewing log data and user behavior to recognize patterns of suspicious activity and implement proactive defenses.