0days

A 0-day, or zero-day, refers to a vulnerability in a piece of software or hardware that is unknown to the vendor or developer responsible for its protection. This means there is no patch or fix available to address the flaw, making systems vulnerable until one is developed and deployed. The term "zero-day" signifies that the developers have had zero days to fix the issue once it becomes publicly known or exploited.

Exploitation of 0-days can occur through various means, including malware, phishing attacks, or direct intrusion into systems. The impact can range from data theft and system disruption to complete compromise. Because there is no immediate defense, 0-day exploits are highly prized by malicious actors, including cybercriminals and state-sponsored hacking groups. They are also of interest to security researchers and intelligence agencies who may use them for defensive or offensive purposes.

The lifecycle of a 0-day typically involves discovery, exploitation, and eventually, the development of a patch. Once a vendor becomes aware of a 0-day vulnerability, they work to create a solution. The period between the discovery of the vulnerability and the release of a patch is critical, during which systems remain at risk. The ethical implications surrounding the discovery and use of 0-days are complex, with ongoing debates about responsible disclosure and the potential for misuse.