What is the CVSS score of EUVD-2026-43812?

EUVD-2026-43812 has a CVSS 3.1 base score of 7.8 (High). CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.4%.

Which versions of Windows NTFS are affected by EUVD-2026-43812?

CVE-2026-49797 is a local code execution vulnerability in the Windows NTFS driver affecting Windows 10 and Windows Server systems organization-wide; no public exploit identified at time of analysis.. A patch is available.

How to fix or mitigate EUVD-2026-43812?

Within 24 hours, inventory all Windows systems running Windows 10 (1607 and later), Windows 11, or Windows Server 2012-2025 to determine organizational exposure to CVE-2026-49797. Within 7 days, deploy the vendor patch from Microsoft to all critical systems, servers, and domain controllers to prevent exploitation through malicious file interactions. Within 30 days, verify complete patch deployment across all affected systems organization-wide to achieve full remediation.

Windows NTFS EUVD-2026-43812

| CVE-2026-49797 HIGH

Heap-based Buffer Overflow (CWE-122)

2026-07-14 microsoft

GHSA-7fcf-6p48-fvvr

Buffer Overflow Heap Overflow Microsoft Windows Server 2012 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 Windows Server 2012 Server Core Installation Windows Server 2012 R2 Windows Server 2012 R2 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:N/UI:R/S:U/C:H/I:H/A:H

CIRCL (temporal)

6.8 MEDIUM

cvss

vuln.today AI

7.8 HIGH

Local NTFS parsing flaw needing a user to open/mount crafted content (AV:L, UI:R), no attacker privileges (PR:N), with full kernel-context code execution giving high C/I/A.

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

4.0 AV:L/AC:L/AT:N/PR:N/UI:P/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

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Generated

Jul 14, 2026 - 18:29 vuln.today

CVE Published

Jul 14, 2026 - 17:05 nvd

HIGH 7.8

DescriptionCVE.org

Heap-based buffer overflow in Windows NTFS allows an unauthorized attacker to execute code locally.

AnalysisAI

Local code execution in the Windows NTFS driver (CVE-2026-49797) allows an attacker with local access to run arbitrary code by tricking a user into interacting with a maliciously crafted NTFS artifact, exploiting a heap-based buffer overflow (CWE-122). The flaw affects a broad range of Windows client and server releases from Windows 10 1607 and Server 2012 through Windows 11 26H1 and Server 2025. Microsoft has released a patch; no public exploit identified at time of analysis and it is not listed in CISA KEV.

Technical ContextAI

The vulnerability resides in NTFS (New Technology File System), the default file system driver in Windows, which runs in kernel mode and parses on-disk metadata structures such as the Master File Table, attributes, and index records. CWE-122 (heap-based buffer overflow) indicates that NTFS allocates a heap buffer and writes past its bounds while parsing attacker-influenced file system data - for example malformed metadata on a crafted volume, disk image, or file. Because NTFS parsing occurs in a privileged kernel context, a controlled heap overflow here can corrupt adjacent kernel objects and lead to arbitrary code execution. The CPE data enumerates Microsoft Windows 10 (1607, 1809, 21H2, 22H2), Windows 11 (24H2, 25H2, 26H1), and Windows Server 2012 through 2025 as affected products.

RemediationAI

Apply the Microsoft security update for CVE-2026-49797 via the MSRC advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-49797; a vendor patch is available, and administrators should deploy the corresponding monthly cumulative update / KB for each affected Windows 10, Windows 11, and Windows Server 2012-2025 build through Windows Update or WSUS/SCCM. Because exploitation requires user interaction with attacker-supplied NTFS content, compensating controls until patching completes include restricting the mounting of untrusted disk images, VHD/VHDX files, and removable/external NTFS volumes (via Group Policy device installation restrictions), which trades off legitimate removable-media workflows, and educating users not to open or mount untrusted images. Given the broad OS footprint, prioritize patching over workarounds, as no configuration change fully removes the NTFS parsing exposure.