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CVE-2026-40377: CWE-122: Heap-based Buffer Overflow in Microsoft Windows 10 Version 1607

0
High
VulnerabilityCVE-2026-40377cvecve-2026-40377cwe-122
Published: 05/12/2026 (05/12/2026, 16:58:40 UTC)
Source: CVE Database V5
Vendor/Project: Microsoft
Product: Windows 10 Version 1607

Description

Heap-based buffer overflow in Windows Cryptographic Services allows an authorized attacker to elevate privileges locally.

CVSS v3.1

Score 7.8high

Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Affected software

Microsoft

Windows 10 Version 1607

Affected versions
>=10.0.14393.0 <10.0.14393.9140

Microsoft

Windows 10 Version 1809

Affected versions
>=10.0.17763.0 <10.0.17763.8755

Microsoft

Windows 10 Version 21H2

Affected versions
>=10.0.19044.0 <10.0.19044.7291

Microsoft

Windows 10 Version 22H2

Affected versions
>=10.0.19045.0 <10.0.19045.7417

Microsoft

Windows 11 version 23H2

Affected versions
>=10.0.22631.0 <10.0.22631.7079

Microsoft

Windows 11 Version 23H2

Affected versions
>=10.0.22631.0 <10.0.22631.7219

Microsoft

Windows 11 Version 24H2

Affected versions
>=10.0.26100.0 <10.0.26100.8457

Microsoft

Windows 11 Version 25H2

Affected versions
>=10.0.26200.0 <10.0.26200.8457

Microsoft

Windows 11 version 26H1

Affected versions
>=10.0.28000.0 <10.0.28000.2113

Microsoft

Windows Server 2012

Affected versions
>=6.2.9200.0 <6.2.9200.26079

Microsoft

Windows Server 2012 (Server Core installation)

Affected versions
>=6.2.9200.0 <6.2.9200.26079

Microsoft

Windows Server 2012 R2

Affected versions
>=6.3.9600.0 <6.3.9600.23181

Microsoft

Windows Server 2012 R2 (Server Core installation)

Affected versions
>=6.3.9600.0 <6.3.9600.23181

Microsoft

Windows Server 2016

Affected versions
>=10.0.14393.0 <10.0.14393.9140

Microsoft

Windows Server 2016 (Server Core installation)

Affected versions
>=10.0.14393.0 <10.0.14393.9140

Microsoft

Windows Server 2019

Affected versions
>=10.0.17763.0 <10.0.17763.8755

Microsoft

Windows Server 2019 (Server Core installation)

Affected versions
>=10.0.17763.0 <10.0.17763.8755

Microsoft

Windows Server 2022

Affected versions
>=10.0.20348.0 <10.0.20348.5139

Microsoft

Windows Server 2022, 23H2 Edition (Server Core installation)

Affected versions
>=10.0.25398.0 <10.0.25398.2330

Microsoft

Windows Server 2025

Affected versions
>=10.0.26100.0 <10.0.26100.32860

Microsoft

Windows Server 2025 (Server Core installation)

Affected versions
>=10.0.26100.0 <10.0.26100.32860

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 08/11/2026, 16:46:08 UTC

Technical Analysis

This vulnerability involves a heap-based buffer overflow in the Windows Cryptographic Services component of Windows 10 Version 1607. An attacker with local authorized access can exploit this flaw to elevate their privileges, potentially gaining higher system rights. Microsoft has published an official fix addressing this issue.

Potential Impact

An authorized local attacker can exploit this vulnerability to elevate privileges, potentially gaining higher-level access on the affected system. This could lead to full system compromise depending on the privileges obtained.

Mitigation Recommendations

An official fix is available from Microsoft. Users and administrators should apply the security update provided by Microsoft for Windows 10 Version 1607 to remediate this vulnerability. Refer to the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40377 for detailed patching instructions.

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Technical Details

Data Version
5.2
Assigner Short Name
microsoft
Date Reserved
2026-04-11T23:06:15.615Z
Cvss Version
3.1
State
PUBLISHED
Remediation Level
official-fix
Vendor Advisory Urls
[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40377","vendor":"Microsoft"}]

Threat ID: 6a036554cbff5d861008c959

Added to database: 05/12/2026, 17:37:24 UTC

Last enriched: 08/11/2026, 16:46:08 UTC

Last updated: 09/14/2026, 22:01:33 UTC

Views: 66

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