A vulnerability in hardware or software of which is unknown to the manufacturer/ developer or general public. The name “zero day” references the number of days that the software or hardware vendor has known about a vulnerability. As zero-day vulnerabilities are unpatched and unknown, they are often used as the basis for more complex attacks. Zero-days are often used sparingly by attackers, as they get “used up” once they are publicly exposed and patched by the vendor.

A vulnerability in hardware or software of which is unknown to the manufacturer/ developer or general public. The name “zero day” references the number of days that the software or hardware vendor has known about a vulnerability. As zero-day vulnerabilities are unpatched and unknown, they are often used as the basis for more complex attacks. Zero-days are often used sparingly by attackers, as they get “used up” once they are publicly exposed and patched by the vendor.