Description
A denial of service vulnerability exists in the Windows implementation of Transport Layer Security (TLS) when it improperly handles certain key exchanges. An attacker who successfully exploited the vulnerability could cause a target system to stop responding. To exploit this vulnerability, a remote unauthenticated attacker could send a specially crafted request to a target system utilizing TLS 1.2 or lower, triggering the system to automatically reboot. The update addresses the vulnerability by changing the way TLS key exchange messages are validated.
Affected products
microsoft: windows 10; microsoft: windows server 2019
References2
Metrics
- CVSS 3.1
-
8.6
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H - EPSS — exploit probability
- 15% percentile: 97 · as of 11 November 2026
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.