EUVD-2026-44079
GHSA-jh9g-j7qf-9cm4
Severity by source
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Local authenticated low-priv attacker (AV:L/PR:L); use-after-free requires a race/grooming so AC:H; kernel boundary crossing gives S:C with full C/I/A impact.
Primary rating from Vendor (microsoft).
CVSS VectorNVD
Lifecycle Timeline
2DescriptionNVD
Use after free in Microsoft Windows allows an authorized attacker to elevate privileges locally.
AnalysisAI
Local privilege escalation in Microsoft Windows (Windows 10 1607 through Windows 11 26H1 and Windows Server 2012 through 2025) arises from a use-after-free memory-corruption flaw (CWE-416) that lets an already-authenticated local user run code at elevated privilege. The CVSS 3.1 base score is 7.8 with a scope-changed vector, and Microsoft has shipped a fix via MSRC. There is no public exploit identified at time of analysis and the issue is not listed in CISA KEV, so exploitation is currently theoretical rather than observed.
Technical ContextAI
The root cause is a use-after-free (CWE-416): a component frees a kernel or driver object while a dangling reference remains, and subsequent reuse of that freed memory lets an attacker control object contents or function pointers to hijack execution in a higher-privileged context. The CPE set spans the client kernels of Windows 10 (1607/1809/21H2/22H2) and Windows 11 (24H2/25H2/26H1) plus the full Server line (2012, 2012 R2, 2016, 2019, 2022, 2025, including Server Core installations), which indicates the defect lives in shared Windows core/kernel-mode code rather than an edition-specific feature. The tags also flag Memory Corruption and Denial Of Service, consistent with a freed-object condition that can either be groomed into code execution or simply crash the affected subsystem.
RemediationAI
Patch available per vendor advisory - apply the Microsoft security update for CVE-2026-50476 through Windows Update / WSUS / your standard patch-management channel, selecting the cumulative update matching each affected build; consult the per-product fixed versions listed at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50476 (no single universal version number applies because each OS build ships its own KB). Because the attack requires an authenticated local user, compensating controls until patching completes include tightening local logon rights and removing unnecessary interactive/local accounts to shrink the population of would-be attackers, enforcing least privilege so fewer processes run as exploitable low-privilege footholds, and monitoring EDR for anomalous privilege transitions and kernel-object abuse - with the trade-off that these reduce but do not eliminate exposure since any legitimate local user retains the prerequisite access. Prioritize Server Core and multi-user/RDS hosts where untrusted users share a machine.
More in Windows 10 Version 1607
View allRemote code execution in Windows IKE Extension (Internet Key Exchange) via double free memory corruption allows unauthen
Local privilege escalation in Microsoft Active Directory Federation Services (AD FS) lets an already-authenticated low-p
Windows Shell protection mechanism failure (CVE-2026-32202) allows remote attackers to perform spoofing attacks over a n
Local privilege escalation in the Microsoft Windows Kernel allows an unauthorized attacker to gain elevated (SYSTEM-leve
Local code execution in the Windows DHCP Client service stems from a use-after-free (CWE-416) memory-corruption flaw aff
Remote code execution in the Microsoft Windows DHCP Server role allows an unauthenticated network attacker to run arbitr
Local code execution in the Windows Media component of supported Windows 10, Windows 11, and Windows Server (2016 throug
Local privilege escalation via heap-based buffer overflow in the Windows Message Queuing (MSMQ) Queue Manager component
Local privilege escalation in Microsoft Windows Win32K lets an authenticated low-privileged user corrupt kernel heap mem
Local privilege escalation in the Windows NTFS file system driver lets an authenticated low-privileged user win a race c
Elevation of privilege in the Windows Hyper-V virtual network switch (VMSwitch) lets an authenticated attacker operating
Remote code execution in Microsoft Windows Remote Desktop (RDP) allows an unauthorized network attacker to run arbitrary
Same weakness CWE-416 – Use After Free
View allSame technique Use After Free
View allShare
External POC / Exploit Code
Leaving vuln.today