nollapäivähyökkäys

Nollapäivähyökkäys, often abbreviated as zero-day attack or zero-day exploit, refers to a cybersecurity threat that exploits a vulnerability in software or hardware that is unknown to the vendor or developer responsible for the affected system. The term "zero-day" signifies that the vendor has had zero days to fix the vulnerability since it was discovered or exploited.

These attacks are particularly dangerous because there are no immediate patches or defenses available when they are first launched. Attackers can leverage these unknown flaws to gain unauthorized access, steal data, disrupt services, or install malicious software without the users or organizations having any prior warning or protection. The discovery of a zero-day vulnerability can be accidental or the result of dedicated research by malicious actors.

Once a zero-day exploit is identified, cybersecurity professionals work rapidly to understand the vulnerability and develop a solution. The vendor typically releases a patch or update to address the flaw. However, the period between the exploitation of a zero-day and the availability of a fix can be a critical window for attackers to cause significant damage. The existence of zero-day vulnerabilities highlights the ongoing challenge of securing complex software and hardware systems against evolving threats.