The term zero-day exploit originates from the fields of cybercrime, cybersecurity and digital transformation. It refers to a security vulnerability in software or systems that is not yet known - neither to the manufacturer nor to the public. "Zero-day" means that there are zero days to react to the problem and develop protective measures.
If an attacker exploits this unknown vulnerability, it is referred to as a zero-day exploit. Criminals often use such vulnerabilities to infiltrate malware, steal data or manipulate systems unnoticed. As the software manufacturer is not yet aware of the vulnerability, there is no protection or security update at this time.
An example: A company uses a popular email programme. Hackers discover a previously unknown vulnerability that allows them to gain access to the company network with a perfectly disguised email. Even before the manufacturer can react, sensitive data is already at risk - typical of a zero-day exploit.
For companies, this means that regular updates, fast response times and attention to security alerts are essential in order to provide the best possible protection against such attacks.
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