What is the CVSS score of EUVD-2026-44256?

EUVD-2026-44256 has a CVSS 3.1 base score of 7.8 (High). CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.3%.

Which versions of Windows Kernel are affected by EUVD-2026-44256?

A local privilege escalation vulnerability in Microsoft Windows Kernel (CVE-2026-56644) allows any authenticated user with local system access to gain SYSTEM-level privileges, potentially…. A patch is available.

How to fix or mitigate EUVD-2026-44256?

Within 24 hours, inventory all Windows 10 (versions 1607-22H2), Windows 11 (versions 24H2/25H2/26H1), and Windows Server 2016-2025 systems; identify which systems cannot tolerate patching windows and segregate them for priority remediation. Within 7 days, deploy the available Windows security update to non-production systems to validate compatibility with critical applications and dependencies. Within 30 days, ensure 100% of production systems receive the patch, implementing compensating controls (local account access restrictions, privileged access workstations, enhanced system monitoring) for systems requiring extended patching windows due to business constraints.

Windows Kernel EUVD-2026-44256

| CVE-2026-56644 HIGH

Use After Free (CWE-416)

2026-07-14 microsoft

GHSA-2wqv-j5pw-q5fx

Denial Of Service Use After Free Memory Corruption Microsoft Windows Server 2016 Windows Server 2019 Windows Server 2022 Windows Server 2025 Windows 10 Version 1607 Windows 10 Version 1809 Windows 10 Version 21H2 Windows 10 Version 22H2 Windows Server 2016 Server Core Installation Windows Server 2019 Server Core Installation Windows 11 Version 24H2 Windows 11 Version 25H2 Windows 11 Version 26H1 Windows Server 2025 Server Core Installation

7.8

CVSS 3.1 · Vendor: microsoft

Temporal: 6.8

Severity by source

Vendor (microsoft) PRIMARY

7.8 HIGH

AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CIRCL (temporal)

6.8 MEDIUM

cvss

vuln.today AI

7.8 HIGH

Local privilege escalation requires prior low-privileged code execution (AV:L, PR:L) with no user interaction; kernel-mode compromise yields full C/I/A impact within the unchanged local scope.

3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

4.0 AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Primary rating from Vendor (microsoft).

CVSS VectorVendor: microsoft

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Generated

Jul 14, 2026 - 19:02 vuln.today

CVE Published

Jul 14, 2026 - 17:09 nvd

HIGH 7.8

DescriptionCVE.org

Use after free in Windows Kernel allows an authorized attacker to elevate privileges locally.

AnalysisAI

Local privilege escalation in the Microsoft Windows Kernel allows an authenticated attacker to elevate to SYSTEM by exploiting a use-after-free (CWE-416) memory corruption condition, spanning Windows 10 (1607 through 22H2), Windows 11 (24H2/25H2/26H1), and Windows Server 2016 through 2025. Reported by Microsoft with a CVSS 3.1 base score of 7.8 (AV:L/AC:L/PR:L/UI:N), the flaw grants full confidentiality, integrity, and availability impact on the local system. No public exploit identified at time of analysis, and it is not listed in CISA KEV; a vendor patch is available.

Technical ContextAI

The vulnerability resides in the core Windows Kernel (ntoskrnl-level code), the trusted component that mediates all process scheduling, memory management, and hardware access at the highest privilege ring. The root cause is CWE-416 (Use After Free): a kernel object is freed while a dangling reference remains, and subsequent dereference of that stale pointer lets an attacker manipulate freed-then-reallocated memory. Because the affected code executes in kernel mode, successful control of the freed allocation can be groomed into an arbitrary read/write or controlled-execution primitive. The CPE set confirms the affected surface is the base OS across the Windows 10, Windows 11, and Windows Server product families (client versions 1607-26H1 and Server 2016-2025), not an add-on application, indicating a defect in a shared kernel code path present across supported builds.

RemediationAI

Apply the Microsoft cumulative security update that addresses CVE-2026-56644 for each affected build; the exact fixed build numbers are enumerated per product on the MSRC advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56644 (Patch available per vendor advisory - install the latest monthly cumulative update for your Windows 10, Windows 11, or Windows Server version). Because this is a kernel defect with no configuration toggle, there is no supported feature-level workaround; where immediate patching is not possible, reduce exposure by enforcing least-privilege so fewer local accounts can run code, restricting interactive and remote-desktop logon rights on servers, and deploying kernel-exploit mitigations such as HVCI/Hypervisor-Enforced Code Integrity and Attack Surface Reduction rules to raise the cost of exploitation - noting these controls only lower likelihood and do not remove the vulnerable code, and HVCI can affect compatibility with unsigned or older drivers. Prioritize patching on multi-user, jump-box, and terminal-server systems where untrusted local code is most likely to run.