Checking the server logs to evaluate which emails were sent to <someaddress@domain,com> is the first action the analyst should do to evaluate the potential impact of this security incident. Server logs are records of events or activities that occur on a server, such as email transactions, web requests, or authentication attempts. Checking the server logs can help to determine how many emails were sent to <someaddress@domain,com>, when they were sent, who sent them, and what they contained. This can help to assess the scope and severity of the incident and plan further actions .