A Zero Day Exploit is an unpatched vulnerability or bug unknown to computer programmers and hardware manufacturers
A Zero Day exploit is malicious software designed to work against a particular flaw in computer software, hardware, or IT system called a vulnerability or bug. The vulnerability is unbeknownst to the developer. Zero day refers to the day the vulnerability is discovered, by the rightful hardware or software developer, or anyone else including cyber security researchers or even hackers. A zero day exploit is one that takes advantage of a zero day vulnerability. It may also be called a zero day attack. Zero Day attacks defy antivirus apps and virtual private networks.
Why is it Called a Zero Day Attack?
Day zero is when the vulnerability is first discovered. Each day after that increments the numbering nomenclature. For example, a one-week old bug would be referred to as a seven-day vulnerability. A one-month old vulnerability would be called a thirty-day vulnerability. A zero day attack occurs before the vulnerability is discovered and thus before any security update is developed to fix the vulnerability.
Vulnerabilities can be discovered by anyone, including the developers, the general public, researchers, hackers, and Advanced Persistent Threat Groups. When a vulnerability is discovered, a security patch is developed and released to fix the flaw. Until the security update is made available the hardware or software is subject to zero day exploits or attacks by hackers and malware.
What is a Zero Day Exploit and Why Are They Dangerous?
White hat hackers are ethical hackers who are interested in research, improving cyber security or are part of a bug bounty program. A white hack hacker would most likely inform the developers of the vulnerability, so a security patch can be developed and distributed. Black hat hackers, commonly referred to as simply hackers, take advantage of the vulnerability with zero day exploits while the vulnerability is either not known to the developers or still unpatched. Usually, the goal or a zero day exploit is to control IT systems, conduct espionage, destroy data, or obtain money. Skilled hackers can quickly launch a malware attack that infiltrates computers easier by exploiting the weaknesses of a zero day vulnerability. Because the vulnerability is new, there is no security patch and it is easy for hackers to launch a successful zero day attack.
Examples of Zero Day Exploits
Many high profile cyber attacks were zero day exploits. Security patches are released only after the vulnerability becomes known to developers. If a hacker discovers a zero day vulnerability before the developer does they can launch malware attacks for months or even years before the exploit becomes known to ethical researchers.
- 2017 Democratic National Convention (DNC) Date release
- March 2019 Chrome web browser Chrome CVE-2019-5786 was a zero day exploit in which the host system could be fully compromised
- In 2017 hacker group The Shadow Brokers released a series of US National Security Agency zero day exploit tools that targeted MS Windows
What is Malware?
Malware is any type of malicious software on a computer, IT system, or device, or hardware. Malware has criminal motives. Genres of malware include ransomware, spyware, adware, viruses, worms, or any code that can take control of a system, spy, or steal data. Malware is commonly delivered using phishing emails and frequently involves a social engineering attack.
How to Protect Against a Zero Day Attack
Antivirus programs wont work against a zero day exploit because the exploit is too new to have a security update. However, after the patch is released, antivirus software programs will have a fix available.
- Use Secure Wi-Fi. Public WiFi in retail shops is not secure even if a password is required to access it
- Keeping device operating systems patched
- Keep software up to date by accepting patches
- Using secure (HTTPS) websites even if you are not making a purchase
- Protect data by using a virtual local area networks (LANs)
Michelle writes about cyber security as well as how to protect your data online. She has worked in internet technology for over 20 years Michelle earned a B.S. in Engineering from Rensselaer Polytechnic Institute. She published a guide to Cyber Security for Business Travelers