AI-Driven Solutions to Battle Spear Phishing Attacks AI-Driven Solutions to Battle Spear Phishing Attacks
Cybercrime is one of the most prominent threats facing modern businesses. Even with today’s advanced security technology, breaches are still common,... AI-Driven Solutions to Battle Spear Phishing Attacks

Cybercrime is one of the most prominent threats facing modern businesses. Even with today’s advanced security technology, breaches are still common, largely because of human error. Cybercriminals know this, too, so they target human weaknesses through spear phishing.

What Is Spear Phishing?

Phishing is an attack where cybercriminals trick users into clicking malicious links or revealing sensitive information by posing as trusted parties. It’s so effective that five of the 10 most common cyberattack types are all kinds of phishing. Spear phishing — which affected 74% of organizations in 2022 — is one of the most concerning of these threats.

Whereas most phishing attacks are general messages sent to large groups of people, spear phishing targets specific users. Attackers learn more about their targets to personalize and add more detail to their scams. While it requires more work than conventional phishing, it’s often much more convincing — and successful.

Companies have lost millions of dollars to spear phishing attacks in the past. Now that generative artificial intelligence (AI) makes it easier to craft messages in a certain style or tone, these threats may become all the more common.

How AI Can Defend Against Spear Phishing

Spear phishing can be hard for humans to detect, so AI is an ideal alternative. Here are a few ways businesses can use AI to stop spear phishing attacks.

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Heuristic Analysis

AI can scan users’ inboxes to flag or automatically block messages it believes are spear phishing attempts. One of the most straightforward ways to accomplish this is through heuristic analysis.

In this practice, machine learning models learn to identify phishing attacks by recognizing indicators from known examples. Cybercriminals send an estimated 3 billion phishing emails a day, giving these models significant training datasets. With that much to learn from, it’s fairly easy for AI to learn a few known markers of spear phishing attempts.

Similarly, these models can learn to block or allow certain email domains after learning from malicious and benign examples. Humans can learn to recognize the same indicators, but they’re easy to miss, so AI is the more reliable defense.

TTP Threat Hunting

Tactics, techniques, and procedures (TTP) threat hunting is a more advanced approach to the same concept. Instead of relying on known indicators, these AI models learn the general practices and underlying philosophies cybercriminals use in spear phishing campaigns. That way, they can detect attacks more reliably.

The advantage here is that these AI models can spot phishing attempts even when they don’t feature known malicious addresses or other more obvious factors. Consequently, while training this kind of AI is harder, it helps keep up with changing attack techniques. That’s important because cybercrime evolves quickly — zero-day attacks reached an all-time high in 2023, signifying a massive shift to new attack vectors.

Behavioral Biometrics

AI can also detect and respond to spear phishing through behavioral biometrics. This practice teaches machine learning models to recognize how each authorized user tends to behave, and it can extend to how they write messages. By establishing each person’s unique voice and baseline behavior, it can spot when a message claiming to be a trusted insider likely isn’t.

This technique is also helpful in post-breach responses, as it can detect when an account isn’t behaving like the normal authorized user. Breaches take 286 days to contain on average, so this quick recognition can significantly streamline response timelines.

Automated Breach Detection and Response

Of course, even the most reliable AI won’t be able to stop everything. In these cases, AI-powered automated detection and response systems can identify and contain breaches to minimize the damage.

While prevention is always better than a cure, a quick response can ensure the breach doesn’t disrupt too much. Because AI excels at recognizing aberrant behavior, it can contain potential attacks faster and more accurately than humans. This speed and accuracy lead to $1.76 million in savings compared to companies who don’t use AI breach response.

AI Is an Indispensable Tool Against Spear Phishing

AI makes a big difference in anti-spear phishing measures, from prevention to response. As these attacks become more common, it will become imperative to use AI against them. Manual alternatives are too error-prone and slow to rely on.

Cybercriminals are already using AI to craft more convincing spear phishing attacks. Security personnel must also take advantage of these tools to keep pace. AI may not be a perfect solution, but it’s an important step in the right direction.

Zac Amos

Zac is the Features Editor at ReHack, where he covers data science, cybersecurity, and machine learning. Follow him on Twitter or LinkedIn for more of his work.