What is a 0-day Exploit?

A zero-day attack or threat is an attack that exploits a previously unknown vulnerability in a computer application, meaning that the attack occurs on"day zero"of awareness of the vulnerability.

This means that the developers have had zero days to address and patch the vulnerability. Zero-day exploits (actual software that uses a security hole to carry out an attack) are used or shared by attackers before the developer of the target software knows about the vulnerability.

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