KEVs stands for Known Exploited Vulnerabilities, CISA’s catalog of flaws with evidence of active exploitation in the wild. Unlike a generic CVE list, a KEV entry signals that attackers are already using the vulnerability, so it should be treated as an immediate defensive priority rather than a future risk.
In practice, security teams use KEVs to drive patching, mitigation, and exposure reduction on the systems most likely to be targeted first, especially internet-facing services, VPNs, and edge appliances. If patching is delayed, defenders may need compensating controls such as isolation, filtering, or temporary shutdown. KEVs matter because they turn vulnerability management from counting issues into closing the ones most likely to become an initial access path.