High MSRC-CVE-2026-56649 1 CVE

Windows Network File System Remote Code Execution Vulnerability

Published Jul 14, 2026 · Updated Jul 14, 2026

Vendor: Microsoft

Summary

Impact: Remote Code Execution. Microsoft rating: Important. Not known to be exploited — Exploitation Unlikely. Customer action: Required.

Details

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

Medium 5.9

CVE-2026-56649

Windows Network File System Remote Code Execution Vulnerability

Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Network File System allows an unauthorized attacker to execute code over a network.

Microsoft Windows Server 2019 Windows Server 2019 (Server Core installation) Windows 10 Version 1809 Windows

Jul 14, 2026

Revision history

2026-07-14 #1
Information published.

References

CVE-2026-56649 Windows Network File System Remote Code Execution Vulnerability - HTML
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56649
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