Microsoft Windows 11 Version 26H1 vulnerabilities

CVE-2026-26173 [HIGH] CWE-362 CVE-2026-26173: Concurrent execution using shared resource with improper synchronization ('race condition') in Windo Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.

CVE-2026-54107 [HIGH] CWE-362 CVE-2026-54107: Concurrent execution using shared resource with improper synchronization ('race condition') in Windo Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Win32K allows an authorized attacker to elevate privileges locally.

CVE-2026-50404 [HIGH] CWE-362 CVE-2026-50404: Concurrent execution using shared resource with improper synchronization ('race condition') in Windo Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Media allows an authorized attacker to elevate privileges locally.

CVE-2026-54112 [HIGH] CWE-362 CVE-2026-54112: Concurrent execution using shared resource with improper synchronization ('race condition') in Windo Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Win32K allows an authorized attacker to elevate privileges locally.

CVE-2026-50450 [HIGH] CWE-362 CVE-2026-50450: Concurrent execution using shared resource with improper synchronization ('race condition') in Windo Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Wireless Wide Area Network Service allows an authorized attacker to elevate privileges locally.

CVE-2026-50672 [HIGH] CWE-362 CVE-2026-50672: Use after free in Windows NTFS allows an authorized attacker to elevate privileges locally. Use after free in Windows NTFS allows an authorized attacker to elevate privileges locally.

CVE-2026-54132 [MEDIUM] CWE-122 CVE-2026-54132: Heap-based buffer overflow in Windows Kernel allows an unauthorized attacker to elevate privileges w Heap-based buffer overflow in Windows Kernel allows an unauthorized attacker to elevate privileges with a physical attack.

CVE-2026-50668 [MEDIUM] CWE-122 CVE-2026-50668: Heap-based buffer overflow in Windows NTFS allows an unauthorized attacker to elevate privileges wit Heap-based buffer overflow in Windows NTFS allows an unauthorized attacker to elevate privileges with a physical attack.

CVE-2026-50366 [MEDIUM] CWE-476 CVE-2026-50366: Null pointer dereference in Active Directory Domain Services allows an authorized attacker to deny s Null pointer dereference in Active Directory Domain Services allows an authorized attacker to deny service over a network.

CVE-2026-57976 [MEDIUM] CWE-476 CVE-2026-57976: Null pointer dereference in Active Directory Domain Services allows an authorized attacker to deny s Null pointer dereference in Active Directory Domain Services allows an authorized attacker to deny service over a network.

CVE-2026-55003 [MEDIUM] CWE-908 CVE-2026-55003: Use of uninitialized resource in Windows RDP allows an unauthorized attacker to disclose information Use of uninitialized resource in Windows RDP allows an unauthorized attacker to disclose information over a network.

CVE-2026-58546 [MEDIUM] CWE-908 CVE-2026-58546: Use of uninitialized resource in Windows RDP allows an unauthorized attacker to disclose information Use of uninitialized resource in Windows RDP allows an unauthorized attacker to disclose information over a network.

CVE-2025-21330 [HIGH] CWE-400 CVE-2025-21330: Windows Remote Desktop Services Denial of Service Vulnerability Windows Remote Desktop Services Denial of Service Vulnerability

CVE-2026-50354 [HIGH] CWE-416 CVE-2026-50354: Use after free in Windows Kernel allows an authorized attacker to elevate privileges locally. Use after free in Windows Kernel allows an authorized attacker to elevate privileges locally.

CVE-2026-21240 [HIGH] CWE-367 CVE-2026-21240: Time-of-check time-of-use (toctou) race condition in Windows HTTP.sys allows an authorized attacker Time-of-check time-of-use (toctou) race condition in Windows HTTP.sys allows an authorized attacker to elevate privileges locally.

CVE-2026-50372 [HIGH] CWE-122 CVE-2026-50372: Buffer over-read in Windows Redirected Drive Buffering allows an authorized attacker to elevate priv Buffer over-read in Windows Redirected Drive Buffering allows an authorized attacker to elevate privileges locally.

CVE-2026-32224 [HIGH] CWE-416 CVE-2026-32224: Use after free in Windows Server Update Service allows an authorized attacker to elevate privileges Use after free in Windows Server Update Service allows an authorized attacker to elevate privileges locally.

CVE-2026-26166 [HIGH] CWE-415 CVE-2026-26166: Double free in Windows Shell allows an authorized attacker to elevate privileges locally. Double free in Windows Shell allows an authorized attacker to elevate privileges locally.

CVE-2026-27917 [HIGH] CWE-416 CVE-2026-27917: Use after free in Windows WFP NDIS Lightweight Filter Driver (wfplwfs.sys) allows an authorized atta Use after free in Windows WFP NDIS Lightweight Filter Driver (wfplwfs.sys) allows an authorized attacker to elevate privileges locally.

CVE-2026-45640 [HIGH] CWE-416 CVE-2026-45640: Use after free in Windows Bluetooth Port Driver allows an authorized attacker to elevate privileges Use after free in Windows Bluetooth Port Driver allows an authorized attacker to elevate privileges locally.