Whaling Attacks: What They Are and How to Stop Them

Whaling Attacks: What They Are and How to Stop Them

Some cybercriminals see the internet as a vast digital ocean and its users as clueless fish waiting to get caught in their nets. But in this ocean, there are also large whales in the form of senior executives, whose high-ranking positions make targeting them worth the kind of effort Captain Ahab put into catching Moby Dick.

Indeed, the most determined cybercriminals can spend days, weeks, and even months on the digital ocean, patiently observing their targets, researching the perfect bait, and waiting for the right moment to throw it into the water. This makes whaling attacks extremely dangerous, and it's why all organizations need to proactively protect their senior executives against them.

What are Whaling Attacks?

A quick definition of whaling in cybersecurity: Whaling attacks are highly targeted social engineering scams aimed at tricking high-level executives into doing something that's against their best interest.

Just like other social engineering scams, whaling attacks don't necessarily require the same deep technical knowledge as, let's say, zero-day attacks do. Despite the lower barrier to entry, they can still be incredibly effective, damaging, and profitable, which is why they're becoming increasingly common, no longer targeting only senior executives working for the largest enterprises in the world.

In a typical whaling attack, a senior executive receives a seemingly legitimate email message from a trusted contact, such as the company's finance department or IT administrator. The message will urge the executive to perform some reasonably sounding request, such as authorizing a payment, changing a password, or perhaps providing their personal information. Of course, the request is actually malicious—something most victims of whaling find out only when it's too late.

Whaling Attacks Versus (Spear-)Phishing Attacks

Whaling is a type of phishing attack that's aimed at large whales like senior executives instead of small fish like frontline workers. Whereas cybercriminals performing regular phishing attacks are playing the numbers game by casting wide nets, whaling attacks involve a technique called spear-phishing.

As the name of this technique suggests, spear-phishing is far more precise than regular phishing, with attackers honing in on specific targets, hitting them with personalized messages instead of generic ones. The extra effort it takes to craft personalized messages is well worth it to cybercriminals because a single whale can easily be more valuable than hundreds of small fish.

Consequences of Whaling Attacks

The consequences of whaling attacks can be severe and far-reaching, affecting not only the high-ranking targeted individual but also the company the individual works for. Some of the most common consequences include:

  • Financial losses: A significant percentage of whaling attacks are motivated by financial fraud and related crimes. Senior executives frequently receive fake invoices and money transfer requests, and they don't always double- or triple-check their validity. That's exactly how one company in Omaha lost $17.2 million in a series of wires to a bank in China.
  • Loss of sensitive information: In some cases, cybercriminals launch whaling attacks not because they want to make money but because they want to steal sensitive information (such as customer data) and use it to go after even larger targets. Sensitive information may also become lost as an unfortunate side-effect of a destructive whaling attack.
  • Reputational damage: Every whaling attack that's not successfully mitigated results in some reputational damage to the targeted individual and the organization the individual works for. The reputational damage can then lead to loss of business opportunities, credibility, and trust.

To avoid these and other consequences of whaling attacks, it's important to invest in their prevention. By doing so, organizations can minimize the risk of becoming their victims and protect their assets and reputation.

How to Prevent Whaling Attacks?

As with all social engineering attacks, whaling prevention should focus largely on strengthening the weakest link of the cybersecurity chain—the human element—but it doesn't have to stop there. Let's take a closer look at five proven strategies that can significantly decrease the likelihood of a successful whaling attack.

1.      Conduct Cybersecurity Awareness Training

The most effective step any organization can take to prevent whaling attacks is to educate its key employees about the threat by conducting regular cybersecurity awareness training sessions. Such employees need to understand how important it is to maintain a healthy level of suspicion even when reading messages that seem to come from trusted contacts. Furthermore, high-profile employees (or any employees for that matter) should never share any personal information on social media that could be used as potential bait.

2.      Implement Strong Email Security and Authentication

Most whaling attacks come in the form of email messages, so organizations should focus on preventing them from reaching their employees' inboxes by implementing anti-spam and anti-malware software solutions. They should also implement commonly used email standards (SPF, DKIM, and DMARC) to prevent cybercriminals from spoofing their organization and domain.

3.      Enable Multi-Factor Authentication

Multi-factor authentication (MFA) can add an extra layer of security that acts as an additional lock. In practice, this means requiring a second form of authentication, such as a fingerprint, a code sent to a mobile device, or a security token, so that a cybercriminal won't be able to access sensitive data and systems without that second form of authentication even if they somehow trick a senior employee into sharing their login credentials.

4.      Closely Monitor Financial Transactions

Cybercriminals often target senior executives because they are the ones who approve large financial transactions. Transactions that exceed a certain amount, are made outside of regular business hours, or sent to an unknown recipient should always be flagged by an automated system and manually verified. This way, it's possible to catch whaling attacks before they cause significant financial damage.

5.      Report Detected Whaling Attacks

Last but not least, it's important to report any detected whaling attack to the Federal Trade Commission and the Cybersecurity and Infrastructure Security Agency. While this won't prevent the original attack from causing damage, it can go a long way in preventing future similar attacks on other employees and organizations.


There are many cybercriminals who are willing to go to great lengths when going after large whales. However, a truly determined whale is anything but easy to catch, as Captain Ahab famously learned in Moby-Dick. By following the strategies outlined above, you can greatly reduce the risk of becoming a victim of a whaling attack. If you need help with their implementation, you can contact us at BCA IT, and we'll be happy to assist.