Zero-Day Attack
Cyberattacks exploiting previously unknown vulnerabilities before vendors can develop and deploy patches.
Overview
Zero-day attacks are among the most dangerous threats because no patch or signature exists to defend against them. The term 'zero-day' refers to the fact that developers have had zero days to fix the vulnerability. These attacks are highly valuable - nation-states and sophisticated criminals pay millions for zero-day exploits. Organizations are particularly vulnerable during the window between vulnerability discovery and patch deployment. Defense requires multiple layers: behavioral detection, network segmentation, least-privilege access, and rapid incident response. AI-powered systems can sometimes detect zero-day attacks by identifying anomalous behavior patterns.
Real-World Examples
- ▸Exploitation of unknown software vulnerabilities
- ▸Novel attack techniques bypassing all defenses
- ▸Unpatched security flaws in widely-used software
Related Terms
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