What Is a Zero-Day Exploit? And How to Defend Yourself in 2019

Joe Michalowski
Posted: March 13, 2019

You kept your antivirus software up-to-date. You had a firewall in place. Your employees went through all necessary cybersecurity awareness training.

And yet, your company still experienced a security incident. Now, you’re left wondering—what is a zero-day exploit (and how did it get past my cyber defenses)?

Don’t just chalk an attack up to bad luck. With the right tools, you can defend against zero-day exploits and keep your business protected.

Understanding Zero-Day Exploits

A zero-day exploit is an attack that targets a new, unknown weakness in software. Because the vulnerability is unknown, your software and security solutions won’t be patched in time to stop an attacker from capturing the low-hanging fruit.

Studies have shown that zero-day exploits account for 30% of all malware. Sophisticated attackers know that companies and software providers are more vigilant than ever in identifying and patching vulnerabilities. But with a zero-day exploit, none of that vigilance matters.

Even if a vulnerability is spotted and reported quickly, cyber attackers can launch threats faster than patches are released. And it only takes one successful zero-day exploit to compromise your entire network.

The problem is that the market for zero-day exploits is self-sustaining. Attackers that discover coding vulnerabilities can develop zero-day exploits and sell them for as much as $250,000—either to other attackers, state-sponsored actors, or software vendors.

While staying on top of software patching is an essential factor in defending against zero-day exploits, it’s not enough. To protect your network against zero-day threats, you need antivirus that goes beyond traditional capabilities.

Real-Time Protection Against Zero-Day Exploits

Traditional antivirus software falls short against zero-day exploits because they’re signature-based. When new viruses are discovered, your antivirus vendor codes a signature to protect against it. Then, when that signature is scanned later, the virus is blocked from getting into your network.

By definition, zero-day exploits are dangerous because your antivirus software doesn’t have signatures in place to identify them. Until the vulnerability is identified and patched, zero-day exploits can get through traditional antivirus software undetected.

That’s why real-time protection is essential to modern antivirus software. Even the most basic programs today should have on-demand scanning and real-time protection to address zero-day threats before they can compromise your network.

Even though every antivirus vendor knows the dangers of zero-day exploits, not all software is created equal when it comes to defending against them. Any time you’re evaluating antivirus software, you can’t forget to include a careful examination of zero-day exploit protection.

But finding the right antivirus software (and zero-day exploit protection) can be easier said than done. That’s why we put together our guide to the best antivirus programs of 2019.

About the Author

Joe Michalowski
Joe Michalowski

Joe Michalowski covers B2B tech topics including cybersecurity, digital transformation, IT infrastructure, and more.