CVE-2026-45657

This is a mistake in how Windows kernel memory is handled: the system keeps a reference to something it has already released, and then an attacker can trick it into using that freed space. A good analogy is using a key you already threw away—if someone finds a way to get you to open the wrong door, they may be able to take control.

This matters to you if you use or run Microsoft Windows (including Windows 11 and Windows Server) on machines connected to a network. The affected systems listed are microsoft windows 11 23h2, microsoft windows 11 24h2, microsoft windows 11 25h2, microsoft windows 11 26h1, microsoft windows server 2022, and microsoft windows server 2025.

This is RED because the press indicates it is being exploited in the wild (“itw”), meaning attackers may already be attempting it against real targets. Even though public exploit details may not be widely available yet, the combination of a critical kernel flaw and active exploitation makes fast action important.