What is a whaling attack?

Unlike wholesale credential theft attacks against workforces and clients, whaling attacks have high pay-offs for perpetrators. Normal users may have limited network privileges. By contrast, whaling attacks can expose an entire network by compromising a single user.

What is the difference between phishing, spear phishing, and whaling?

Whaling is related to other social engineering techniques like phishing attacks and spear phishing. However, security experts treat whaling as a separate form of social engineering attack. It's important to understand how whaling differs when assessing risks and putting in place protection.

Key takeaway: Phishing refers to all attacks that deceive employees into taking risky actions. Spear phishing is targeted or personalized phishing, while whaling focuses on stealing credentials from high-level employees.

At the general level, phishing attacks rely on spam emails and cold calls to identify and contact targets. They may use malware-infected attachments or fake websites to extract data after identifying suitable targets.

Spear phishers research their victims in detail. Spear phishing attacks may feature personalized sales pitches, fake messages from trusted clients, or spoofed requests from colleagues.

A spear phishing attack aims to persuade victims that criminals are legitimate contacts. This requires careful research to understand victims. Attackers profile targets based on public information and data circulating on the Dark Web, then use profiles to craft realistic scripts and messaging campaigns.

A whaling attack is essentially a form of spear phishing focused on executives and other senior officeholders. However, the role of senior employees separates whaling from conventional phishing and requires specific prevention measures.

How does a whaling attack work?

A whaling attack relies on deception and carelessness. Spear phishers may use malware in their attacks, but advanced tools are often not required. Instead, attackers persuade their victims to provide credentials or make payments.

Many whaling attacks start with phishing attempts to establish email communication between criminals and victims. Unlike most phishing messages, a whaling phishing email is tailored to the recipient. Attackers spend weeks monitoring their victims and researching their contacts.

The email arriving in the target's inbox looks familiar. The attacker may imitate internal colleagues, using cleverly researched email templates and wording. They might pose as a regular client or a LinkedIn contact, using small details to build credibility. Criminals can also hijack internal accounts, making detection even harder.

At the early stage, whalers don't try to force a response. The initial stages of a whaling attack contact victims and start the social engineering process.

Attackers are ready for prolonged interactions with their victims. Email exchanges could last for weeks or months. The attacker may be active on social media, adding credibility to their fake persona. Some criminals also use AI processing to make believable phone calls.

Interaction continues until criminals choose to act. At this point, attackers could make several moves:

• Inviting targets to share documents: Attackers ask victims to share confidential data or credentials via secure document-sharing platforms. This bypasses network security systems, allowing criminals to extract valuable information.
• Making fraudulent payments: Attackers ask victims to make payments into their accounts. For example, attackers may pose as trusted vendors and fraudulently request payment for recently delivered products.
• Increasing urgency: Attackers quickly escalate their tone, requesting urgent action from their contacts. This technique often waits for global events like pandemics or oil price spikes. Major events create a sense of panic, leading to rash decisions.

In all cases, whaling phishing attacks build trust and create a false sense of security. Targets do not know they are under attack until it is too late.

Who are the targets of whaling phishing attacks?

Whalers target high-level individuals of all types. Financial directors, CEOs, COOs, departmental managers, and Chief Security Officers—everyone could become a whaling attack victim.

For example, cybercriminals target C-Suite officers who can authorize payments or enable financial data extraction. Personnel Officers may provide access to employee databases, while Sales Executives allow access to client data. The target depends on what attackers hope to achieve.

Attackers take several factors into account when choosing their targets:

• Access: Attackers focus on individuals with extensive network privileges. This enables attackers to bypass security measures, infiltrate network assets, and steal data.
• Information: Whaling attacks also target individuals with active social media profiles and many known contacts. This gives attackers plenty of information to research victims, build profiles, and pose as legitimate contacts.
• Security: Attackers also target companies with questionable security records. They understand that executives at these firms probably do not follow security best practices.

It's important to note that corporate executives are actually more likely to become cyber-attack victims than ordinary employees.

One study found that over 33% of executives admitted believing a phishing email, while only 8% of ordinary workers gave the same answer. This showcases the skills of attackers. It also shows how vulnerable organizations are at senior levels.

Examples of whaling attacks

The whaling attack template outlined appears regularly in the real world. As these case studies show, high-ranking executives have long been a cybersecurity weak spot for giant corporations and public bodies. As AI develops, the problem is likely to become more serious.

Google and Facebook fall for fake invoice scams

Between 2013 and 2015, a Lithuanian cybercriminal extracted over $100 million from Facebook and Google via fake invoice scams.

In one of the costliest whaling phishing attacks, Evaldas Rimasauskas posed as a Taiwanese hardware supplier. Rimasauskas created a fake website for Quanta Computer and built a convincing web of bogus contracts, emails, and invoices.

Staff at both tech giants agreed to wire transfers to the cybercriminal's foreign accounts, and even though Rimasauskas was finally arrested, similar invoice scams remain common.

The FACC Fake President attack

In 2015, finance staff at Austrian aviation components manufacturer FACC received an email from someone claiming to be the company's CEO. Convinced by the language and tone of the email, a senior financial controller agreed to make a $59.5 million wire transfer for "acquisition projects." Unfortunately, the email actually came from an imposter, and the money was lost in a network of foreign accounts.

The FACC case is a classic business email compromise (BEC) attack, where criminals breach email accounts to research contacts and profile targets.

The WPP Deepfake attack

The BEC is just one whaling phishing technique among many. In 2024, advertising company WPP disclosed that attackers had targeted its CEO with deep-faked voice messages.

In this case, phishers set up a fake WhatsApp account for the CEO and used it to set up a phony Teams meeting with another executive. During the meeting, the attackers used AI processing to mimic the CEO's voice and manipulated YouTube footage to create convincing visuals.

The WPP attack failed. However, it shows how whaling attack methods are developing. Criminals can compromise routine video meetings and phone calls—a threat that is growing as AI becomes more sophisticated.

How to protect corporate leaders against whaling attacks

Whaling phishing attacks rely on human error. As a result, 100 percent prevention is almost impossible. However, security teams can minimize whaling attack risks by implementing robust security measures. Here are some best practices to integrate into your anti-whaling strategy.

Prioritize whaling in cybersecurity training

Educating staff to identify whaling attack risks is critical. Create separate training packages for senior employees that foreground whaling techniques.

Integrate role-playing exercises into cybersecurity training. These exercises are effective because they demonstrate how easy it is to deceive targets. Well-constructed role-plays force executives to question their security knowledge and take a more cautious approach.

However, whaling is not just about C-suite executives. Whaling phishing attacks also imitate senior staff and convince employees to make transfers or provide credentials. All employees need training in how to verify contacts and authorize payments.

Authenticate financial transactions

Implement multi-factor authentication for all financial transactions or transfers of sensitive information. Contacts must provide a unique identifier for sensitive requests, and authentication should block transfers if they cannot do so.

Authentication must apply to all situations. Remember that whaling phishing attacks often use urgency to create a sense of panic. Ensure staff authenticate payments in all cases, even if time seems short.

Exercise caution when curating social media feeds

Whaling phishing attacks feed on publicly available information about high-value targets. Social media is a critical source of details about a target's professional contacts, duties, accomplishments, and even their personal life.

Security teams should educate executives about how attackers use platforms like LinkedIn and X. A checklist with security basics may also be helpful. For example, the checklist could include "avoid posting travel plans" or "don't share project details."

A good rule is to avoid posting personal content wherever possible. Employees should verify the identity of the social media users they interact with, and apply Zero Trust principles. Never assume a social media contact is genuine, particularly if they engage in unprompted messaging chains or ask for further contact details.

Screen malicious websites with web protection

Phishers often lure targets to convincing but fake versions of legitimate websites. Web protection tools guard against this risk.

Threat protection tools rely on databases and various external sources to identify malicious websites before you visit them. If a site raises red flags, web protection tools block access. This doesn't just block malware. If contacts divert you to harmful sites, they may not be who they claim to be.

Web protection also combines with download protection tools that scan attachments and other incoming files. That way, employees boost their email security by blocking malicious embedded malware.

These tools slot into executive workflows. Whaling targets can automatically activate threat protection when they browse the web, and scans operate in the background.

Protect critical assets against whaling attacks

Whaling phishing is a constant cybersecurity threat to all organizations. Attackers understand the value of targeting executives, while high-level corporate officers don't always follow security best practices.

Guard against whaling attack risks by training staff to identify phishers. Implement tools like multi-step authentication, email security, and web protection, and monitor social media usage to minimize the amount of public information available to cybercriminals.