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EPSS 0.8%top 46%

CVE-2026-40415: CWE-416: Use After Free in Microsoft Windows 10 Version 1809

0
High
VulnerabilityCVE-2026-40415cvecve-2026-40415cwe-416
Published: 05/12/2026 (05/12/2026, 16:58:46 UTC)
Source: CVE Database V5
Vendor/Project: Microsoft
Product: Windows 10 Version 1809

Description

Use after free in Windows TCP/IP allows an unauthorized attacker to execute code over a network.

CVSS v3.1

Score 8.1high

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

Affected software

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 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, 16:49:29 UTC

Technical Analysis

This vulnerability (CVE-2026-40415) involves a use-after-free condition in the Windows TCP/IP implementation in Windows 10 Version 1809 (build 10.0.17763.0). Exploitation could allow an unauthenticated attacker to execute arbitrary code remotely by sending specially crafted network packets. The vulnerability is classified under CWE-416 (Use After Free). Microsoft has published an official fix to remediate this issue.

Potential Impact

Successful exploitation allows remote code execution without requiring user interaction or privileges, potentially leading to full system compromise. The vulnerability affects confidentiality, integrity, and availability of the affected system.

Mitigation Recommendations

An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40415 to remediate this vulnerability.

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Technical Details

Data Version
5.2
Assigner Short Name
microsoft
Date Reserved
2026-04-13T00:27:50.798Z
Cvss Version
3.1
State
PUBLISHED
Remediation Level
official-fix
Vendor Advisory Urls
[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40415","vendor":"Microsoft"}]

Threat ID: 6a036557cbff5d861008c9d0

Added to database: 05/12/2026, 17:37:27 UTC

Last enriched: 08/11/2026, 16:49:29 UTC

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

Views: 117

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