What Is a Zero-Day Vulnerability Exploit?

A technological security breach can be devastating for the user and for the software developer. Sensitive information can be compromised, and entire companies can be hijacked by zero-day attacks. Learn what these vulnerabilities are and how to avoid attacks.

What are zero-day definitions?

The term zero-day refers to the amount of time that a software developer has to fix an issue. A vendor or developer has just learned of a flaw and has “zero days” to fix it before it can be exploited. There are a few terms that are commonly used alongside zero-day, and they all mean different things in terms of a cyberattack timeline.

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A zero-day vulnerability is a flaw in software programming that has been discovered before a vendor or programmer has been made aware of it. Because the programmers don’t know this vulnerability exists, there are no patches or fixes, making an attack more likely to be successful.
A zero-day exploit is when a malicious individual take advantage of the vulnerability, often by using malware.
A zero-day attack happens when an individual uses their zero-day exploit to attack or compromise an organization, often resulting in data loss and identity theft.

“A zero-day attack happens when an individual uses their zero-day exploit to attack or compromise an organization, often resulting in data loss and identity theft.”

A zero-day vulnerability can wreak havoc on an organization’s sensitive and proprietary information, if discovered by those who would do harm. Since they’re an unknown weakness, it can feel nearly impossible to protect against attacks.

How do zero-day exploit attacks work?

Software developers are constantly looking for vulnerabilities in code that they can fix with patches that will keep malicious individuals out. While these vulnerabilities are unpatched, attackers can take advantage of code and use it to steal information and victimize the users of a specific software.

These attacks can be particularly dangerous because the only people who know about them are the attackers themselves. Once they’ve infiltrated a source code, they can choose to attack immediately or wait for a more opportune time. But as long as the vulnerability is not discovered, it can be exploited and used in a stealthy attack.

How to avoid zero-day threats

While a zero-day vulnerability is often discovered after it’s too late, everyday computer users can use antivirus software with malware detection to keep their personal information safe. Some other tips for keeping your data safe include:

Using a firewall
Limiting how many applications have your personal data saved
Keeping your antivirus software up to date

It’s a smart idea not to underestimate the damage that a zero-day exploit can cause. But limiting the amount of personal information that you share, using a VPN, and staying informed about cybersecurity can go a long way.

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