An exploited flaw is a weakness in software, firmware, or system configuration that an attacker can actively abuse to get in, bypass controls, or run code. The flaw may be a programming bug, a missing patch, a misconfigured service, or an unsafe default setting.
In cyber security, exploited flaws matter because they often provide the first foothold in an intrusion. Attackers look for exposed services, outdated applications, and internet-facing devices with known weaknesses. Once a flaw is exploited, they may install malware, steal credentials, move laterally, or deploy ransomware. Defenders reduce this risk by patching quickly, removing unnecessary exposure, hardening configurations, and monitoring for signs of exploitation such as unusual requests, new processes, or unexpected remote access.