CVE-2026-69676

Kerberos is the Windows method for verifying who you are when accessing network services. This flaw lets an attacker “replay” captured authentication behavior to get past that check. If that bypass works in your environment, it can lead to running attacker-controlled code on the affected Windows device.

This matters if you run or manage Windows 10, Windows 11, or the listed Windows Server versions and those systems can be reached from a network where an attacker could attempt this attack. The attack needs an “authorized attacker” condition (not just random guessing), so it’s most relevant when someone has network presence and the ability to meet the access/credential requirements.

In practice: only act if the attacker can reach the Kerberos authentication path/service on your machines (for example, through a reachable network) and meet the low-privilege/authorized access requirement.

This is RED because it’s a Remote Code Execution vulnerability in a core Windows authentication component, which attackers can use to move from authentication tricks to full code execution. Even though no public exploit code is on record yet and it’s not in CISA KEV, the impact is high and Microsoft has provided fixed versions that should be applied immediately.