Summary
Impact: Remote Code Execution. Microsoft rating: Critical. Not known to be exploited — Exploitation More Likely. Customer action: Required.
Details
How could an attacker exploit this vulnerability?
An attacker could exploit this vulnerability by sending specially crafted malicious traffic to a vulnerable server.
Security updates
10.0.17763.9020 — https://support.microsoft.com/help/5099538
10.0.20348.5386 — https://support.microsoft.com/help/5099540
10.0.19044.7548 — https://support.microsoft.com/help/5099539
10.0.26100.33158 — https://support.microsoft.com/help/5099536
10.0.26200.8875 — https://support.microsoft.com/help/5101650
10.0.28000.2525 — https://support.microsoft.com/help/5101649
10.0.14393.9339 — https://support.microsoft.com/help/5099535
6.2.9200.26226 — https://support.microsoft.com/help/5099445
6.3.9600.23291 — https://support.microsoft.com/help/5099444
Vulnerabilities 1
-
Critical 9.8
Windows Server Network driver Remote Code Execution Vulnerability
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Server Network driver allows an unauthorized attacker to execute code over a network.
Revision history
-
#2
Updated an acknowledgement. This is an informational change only.
-
#1
Information published.
References
-
CVE-2026-56188 Windows Server Network driver Remote Code Execution Vulnerability - HTML
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56188
-
Microsoft Exploitability Index
https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1
-
Microsoft Support Lifecycle
https://support.microsoft.com/lifecycle
-
Common Vulnerability Scoring System
https://www.first.org/cvss