Whaling is a form of spear phishing that attempts to target high-level executives. Las Vegas casinos refer to the big spenders as whales, and casino managers are willing to spend extra time and effort to bring them into their casinos. Similarly, attackers consider high-level executives the whales, and attackers are willing to put in some extra effort to catch a whale because the payoff can be so great. When successful, attackers gain confidential company information that they might not be able to get anywhere else.
As an example, attackers singled out as many as 20,000 senior corporate executives in a fine-tuned phishing attack. The emails looked like official subpoenas requiring the recipient to appear before a federal grand jury and included the executive’s full name and other details, such as their company name and phone number. The emails also included a link for more details about the subpoena. If the executives clicked the link, it took them to a web site that indicated they needed a browser add-on to read the document. If they approved this install, they actually installed a keylogger and malware. The keylogger recorded all their keystrokes to a file, and the malware gave the attackers remote access to the executives’ systems.
Similar whaling attacks have masqueraded as complaints from the Better Business Bureau or the Justice Department. Executives are sensitive to issues that may affect the company’s profit, and these attacks get their attention. Although not as common, some whaling attacks attempt to reach the executive via phone to get the data. However, many executives have assistants who screen calls to prevent attackers from reaching the executive via phone.