A zero day exploit is a cyber attack that occurs on the same day a weakness is discovered in software. At that point, it's exploited before a fix becomes available from its creator.

Initially when a user discovers that there is a security risk in a program, they can report it to the software company, which will then develop a security patch to fix the flaw. This same user may also take to the Internet and warn others about the flaw. Usually the program creators are quick to create a fix that improves program protection, however, sometimes hackers hear about the flaw first and are quick to exploit it. When this happens, there is little protection against an attack because the software flaw is so new.

Organizations at risk from such exploits can employ several means of detection, including using virtual local area networks (LANs) to protect transmitted data, by making use of a firewall, and using a secure Wi-Fi system to protect against wireless malware attacks. Also, individuals can minimize the risk by keeping their operating systems and software up to date or by using websites with SSL (Security Socket Layer), which secures information being sent between the user and the site.