It can be frustrating when a piece of software keeps demanding to update itself with security patches, but they're very important for the safety of your device. When a program keeps itself updated, it protects itself better against the dreaded zero-day attack and keeps you safe.
With that being said, what is a zero-day exploit, and why is it so important to keep your software updated?
What Is a Zero-Day Exploit?
Before we jump into what a zero-day (or 0 day) exploit is, we need to take a look at the world of exploit hunting. It's extremely difficult for a developer to publish software that contains zero bugs; as a result, this creates exploit hunters who want to find these bugs.
An exploit hunter will try different methods to find a hole in the software's defenses. This may include tricking the program into letting the exploiter access the software remotely or forcing it to run a malicious program.
Once the hunter finds an exploit, they can take one of two paths. This depends on their general disposition and their reasons for hunting exploits in the first place.
Fixing a Zero-Day Vulnerability
If the bug hunter is a researcher or an enthusiast, the tale will likely take a good path. In this instance, the exploit hunter will report the bug to the developer in secret to keep the exploit from falling into the wrong hands.
Once the developer knows about the exploit, they can quickly develop and release a patch before anyone else finds out about the bug. Of course, a fix is only useful if the users actually download it, which is why some software will automatically check for and download security patches.
This method of patching can be annoying for you, as a piece of software may begin demanding a patch every day. Nonetheless, it's important to let these updates run, as it might be a developer patching up a zero-day exploit to defend its users.
Exploiting a Zero-Day Vulnerability
The other path, however, doesn't have such a happy ending. If the bug hunter is looking for exploits that they can abuse for themselves, they'll keep that knowledge away from the developer. Then the bug hunter will develop and release a program that exploits the bug for personal gain.
This scenario is particularly nasty, as it's being actively exploited without the developer's knowledge. They can't fix what they don't know about, which gives the cybercriminal free rein over everyone's copies of the software until someone else discovers the bug.
Once the developer becomes aware of an actively-exploited bug, it becomes a race against time. If the developer is quick, they can seal up the bug before any damage is done; if they're not, it could jeopardize customer security.
When a malicious agent finds and exploits a bug, it creates a critical moment in cybersecurity where the two parties race to fix or capitalize the vulnerability. This moment is captured by the term "zero-day exploit." This is because an exploit is developed the same day the bug has been discovered—it's on the "zeroth day."
The Danger of Zero-Day Exploits
Zero-day exploits are dangerous because they have two advantages over the cybersecurity world. Not only do they abuse a bug that has not been patched yet, but they do so without the developer knowing about it until it's too late.
Stuxnet is a particularly nasty example of a zero-day attack. Stuxnet abused an exploit discovered in an Iranian uranium enrichment center. Stuxnet infiltrated the system, forced the centrifuges to spin so quickly that they came apart, then made a false diagnostic report to say everything was okay.
It deliberately went out of its way to fool the users of the system into thinking everything was going smoothly As such, nobody knew anything was wrong until around a thousand centrifuges had torn themselves to shreds.
The nature of a zero-day virus means that it can sneak under the radar with great efficiency. Antiviruses don't catch it, because they don't know what to look for. Software can't defend against it, because it doesn't know it has the flaw to begin with.
This makes a zero-day attack a nasty way for a hacker to do damage without a victim even realizing what's going on.
How to Stay Safe From Zero-Day Vulnerabilities
Zero-day threats definitely sound scary, and they shouldn't be underestimated by any means. However, all is not lost; there are ways you can take care of yourself and prevent a zero-day from infecting your PC.
The best protection against a zero-day virus is a good sense of what not to do on the internet. Malware developers can exploit all the zero-day issues they want, but they still need to get the payload onto your PC in some way. As long as you deny them that, your device is safe from the majority of threats.
In that way, you should definitely learn as much about online security as you can. Not all tips will be relevant for protecting against a zero-day, but you still need to know how to browse safely.
If you've already got the basics down, there's a lot you can do to protect yourself from a zero-day exploit. These exploits work best on systems that aren't regularly updated, so downloading a zero-day patch as soon as it's ready is a fantastic way to stay safe.
Becoming a Hero vs. Zero-Day Threats
A zero-day threat can be a major cybersecurity issue, but that doesn't mean you're totally helpless against them. Now, you know what a zero-day threat is, why they're so dangerous, and why it's important to keep all of your software up-to-date, no matter how annoying the update prompts are.
Ensuring your PC is safe from cyberattacks can put your head in a spin. Fortunately, if you follow a few basics do's and don'ts, you'll be safe from the majority of threats online.