Critical CVSS 9.9 2026-07 archive

Executive Summary

Use after free in Windows VMSwitch allows an authorized attacker to elevate privileges over a network.

Overview

9.9
CVSS CRITICAL
Critical
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
Category Elevation of Privilege
Released Jul 14 2026
Last Updated Jul 14 2026
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known

CVSS Vector

ATTACK VECTOR
Network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
Low
USER INTERACTION
None
SCOPE
Changed
CONFIDENTIALITY
High
INTEGRITY
High
AVAILABILITY
High
EXPLOIT CODE MATURITY
Unproven
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 8.6

EPSS Score

No EPSS score available for this CVE.

View on FIRST.org

Affected Products

27 affected products
Product KB Article Severity Impact Restart Required
Windows 10 Version 1607 for 32-bit Systems 5099535 (Security Update) Critical Elevation of Privilege Yes
Windows 10 Version 1607 for x64-based Systems 5099535 (Security Update) Critical Elevation of Privilege Yes
Windows 10 Version 1809 for 32-bit Systems 5099538 (Security Update) Critical Elevation of Privilege Yes
Windows 10 Version 1809 for x64-based Systems 5099538 (Security Update) Critical Elevation of Privilege Yes
Windows 10 Version 21H2 for 32-bit Systems 5099539 (Security Update) Critical Elevation of Privilege Yes
Windows 10 Version 21H2 for ARM64-based Systems 5099539 (Security Update) Critical Elevation of Privilege Yes
Windows 10 Version 21H2 for x64-based Systems 5099539 (Security Update) Critical Elevation of Privilege Yes
Windows 10 Version 22H2 for 32-bit Systems 5099539 (Security Update) Critical Elevation of Privilege Yes
Windows 10 Version 22H2 for ARM64-based Systems 5099539 (Security Update) Critical Elevation of Privilege Yes
Windows 10 Version 22H2 for x64-based Systems 5099539 (Security Update) Critical Elevation of Privilege Yes
Windows 11 Version 24H2 for ARM64-based Systems 5101650 (Security Update) Critical Elevation of Privilege Yes
Windows 11 Version 24H2 for x64-based Systems 5101650 (Security Update) Critical Elevation of Privilege Yes
Windows 11 Version 25H2 for ARM64-based Systems 5101650 (Security Update) Critical Elevation of Privilege Yes
Windows 11 Version 25H2 for x64-based Systems 5101650 (Security Update) Critical Elevation of Privilege Yes
Windows 11 Version 26H1 for ARM64-based Systems 5101649 (Security Update) Critical Elevation of Privilege Yes
Windows 11 version 26H1 for x64-based Systems 5101649 (Security Update) Critical Elevation of Privilege Yes
Windows Server 2012 5099445 (Monthly Rollup) Critical Elevation of Privilege Yes
Windows Server 2012 (Server Core installation) 5099445 (Monthly Rollup) Critical Elevation of Privilege Yes
Windows Server 2012 R2 5099444 (Monthly Rollup) Critical Elevation of Privilege Yes
Windows Server 2012 R2 (Server Core installation) 5099444 (Monthly Rollup) Critical Elevation of Privilege Yes
Windows Server 2016 5099535 (Security Update) Critical Elevation of Privilege Yes
Windows Server 2016 (Server Core installation) 5099535 (Security Update) Critical Elevation of Privilege Yes
Windows Server 2019 5099538 (Security Update) Critical Elevation of Privilege Yes
Windows Server 2019 (Server Core installation) 5099538 (Security Update) Critical Elevation of Privilege Yes
Windows Server 2022 5099540 (Security Update) Critical Elevation of Privilege Yes
Windows Server 2025 5099536 (Security Update) Critical Elevation of Privilege Yes
Windows Server 2025 (Server Core installation) 5099536 (Security Update) Critical Elevation of Privilege Yes

Patches

9 patches
Article Type Restart
5099535 Security Update Yes
5099538 Security Update Yes
5099539 Security Update Yes
5101650 Security Update Yes
5101649 Security Update Yes
5099445 Monthly Rollup Yes
5099444 Monthly Rollup Yes
5099540 Security Update Yes
5099536 Security Update Yes

Known Exploits

Acknowledgments

Microsoft Offensive Research & Security Engineering