What might indicate that an attacker is employing a dead-drop method for botnet control?

The indication that an attacker might be using a dead-drop method for botnet control is best represented by the presence of multiple saved draft emails. This behavior aligns with the strategy of dead-drop communication, where the attacker places information in a location that the bot will access and retrieve on its own. By saving drafts in a cloud-based email service, the attacker can neutralize the need for direct communication with the compromised systems. The bots can check these drafts for commands or updates without ever needing to establish a direct, live session, thus minimizing the risk of detection.

This method allows attackers to covertly send instructions while evading some common security measures that might flag more direct communications or noticeable traffic patterns. It is a subtle way to maintain control over compromised machines while ensuring that the communication remains under the radar.

Other potential indicators like frequent password changes, unusual network traffic, or increased firewall alerts may suggest suspicious activity or potential breaches, but they do not specifically point towards the dead-drop method of command and control, which relies on pre-positioned information that bots autonomously retrieve from static locations.