cyber attack

What is a Zero Day Vulnerability?

A Zero Day Vulnerability is an unknown flaw in either software or hardware that can be exploited by those with malicious intent. A zero day vulnerability is typically one that has not been used before, and therefore there has been no patch or fix created to solve the vulnerability. A zero day vulnerability harnesses the element of surprise, and once discovered, there are “zero days” to fix the vulnerability because it has already been exploited.

Once a zero day vulnerability has been exploited, it cannot be used again because the vulnerability will now be known. Once a patch is written and used, the exploit is no longer considered a zero-day exploit. Hackers know that a Zero Day vulnerability must be used wisely

Because of this, a whole market has developed around the purchasing of Zero Day vulnerabilities. Cyber criminals can find unknown vulnerabilities and write viruses and malware specific to that vulnerability. These programs are auctioned off on dark web markets to the highest bidder.

Why initiate a Zero Day Attack?

While software developers are constantly looking to patch security vulnerabilities — we see this in the form of software updates — cyber attackers are constantly seeking to exploit them. And there are many types of cyber attackers, each with their own motivations:

  • Cybercriminals or hackers are often financially motivated
  • Hacktivists are motivated by drawing attention to a cause social or political
  • Corporate espionage artists are motivated by spying on companies
  • Cyberwarfare attackers can be countries or independent malicious actors who want to compromise a cybersecurity infrastructure as an act of war

Common Zero Day Victims

Anyone using an exploited system or software can be the victim of a Zero Day attack. Common victims are:

  • Businesses and Organizations
  • Government Agencies
  • Individuals

If you’re an everyday computer user, a zero-day vulnerability can pose serious security risks because exploit malware can infect operating systems, web browsers, applications, open-source components, hardware, even IoT devices through otherwise harmless web browsing activities. This can include viewing a website, opening a compromised message, or playing infected media.

How to Protect Yourself from Zero-Day Exploits?

Even as we can’t always detect these vulnerabilities, we can protect our devices and data in the event an exploit does occur. Consider these proactive and reactive security measures.

  1. Keep software up to date to ensure security patches are in place and to reduce the risk of malware infection.
  2. Limit your applications because the less you have downloaded, the less data you’re putting at risk.
  3. Use a firewall to monitor and block suspicious activity, such as zero-day exploits.
  4. Educate yourself on zero-day exploits and seek out solutions when zero-day vulnerabilities are discovered.
  5. Consider using antivirus software to protect against both known and unknown threats.

Notable Zero Day Exploits

Finally, don’t underestimate the threat of zero-day exploits. Cybercriminals will seek to exploit security holes and gain access to your devices and your personal information. They can use your information for a range of cybercrimes including identity theft, bank fraud, and ransomware.

Just consider these recent and headline-making examples of zero-day exploits.

  • Google Chrome, 2021: Google Chrome fell victim to several zero-day threats, attributed to a bug in JavaScript.
  • Zoom, 2020: Hackers exploited a vulnerability in the video conferencing platform that allowed them to take remote control over PCs.
  • Apple, 2020: A bug in Apple’s iOS software allowed hackers to compromise devices from remote locations.
  • Microsoft Windows, 2019: Government agencies across Eastern Europe saw their Microsoft Windows software exploited, resulting in suspicious apps being installed, data changed, and programs compromised.
  • Microsoft Word, 2017: Individual computer users saw their bank accounts compromised after opening a Microsoft Word document containing zero-day malware.
  • ​​Stuxnet, 2010: A self-replicating computer worm disrupted Iranian nuclear plants, taking control of computers and altering the speed of centrifuges in the plants, ultimately shutting them down.

Stuxnet isn’t only one of the earliest zero-day exploits used, but it’s also one of the most famous. The zero-day attack was even made into a documentary, appropriately titled “Zero Days.”

Just because zero-day exploits are meant to fly under the radar doesn’t mean you should let these stealthy cyberattacks fall off your own radar. Instead, zero in on cybersecurity best practices to avoid zero-day exploits at all costs.



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