CVE-2026-49177

Windows TCP/IP Information Disclosure Vulnerability

Published Jul 14, 2026 CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed

Description

Out-of-bounds read in Windows TCP/IP allows an authorized attacker to disclose information locally.

Analysis

Technical impact

The vulnerability is an out-of-bounds read in the Windows TCP/IP stack that permits a local, authorized attacker to read arbitrary memory addresses within the kernel. This can expose sensitive data such as passwords, cryptographic keys, or configuration information, thereby compromising the confidentiality of the affected system. The flaw is classified as CWE-125.

Affected Systems

This issue affects Microsoft Windows 10 versions 1607, 1809, 21H2 and 22H2; Windows 11 versions 24H2, 25H2 and 26H1; and Windows Server editions 2012, 2012 R2, 2016, 2019, 2022 and 2025, including both standard and Server Core installations.

Risk and Exploitability

The CVSS base score of 5.5 designates the vulnerability as medium severity, while the EPSS score of less than 1 % indicates a very low probability of exploitation in the wild. The vulnerability is not listed in the CISA KEV catalog. Successful exploitation requires local authorized access, such as that granted to an administrator or a compromised user account. The out-of-bounds read could be triggered by kernel or user-mode components that interact with the network stack.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Microsoft

Windows 10 Version 1607

affected

Version	Status	Constraints
`10.0.14393.0`	affected	< 10.0.14393.9339

Microsoft

Windows 10 Version 1809

affected

Version	Status	Constraints
`10.0.17763.0`	affected	< 10.0.17763.9020

Microsoft

Windows 10 Version 21H2

affected

Version	Status	Constraints
`10.0.19044.0`	affected	< 10.0.19044.7548

Microsoft

Windows 10 Version 22H2

affected

Version	Status	Constraints
`10.0.19045.0`	affected	< 10.0.19045.7548

Microsoft

Windows 11 Version 24H2

affected

Version	Status	Constraints
`10.0.26100.0`	affected	< 10.0.26100.8875

Microsoft

Windows 11 Version 25H2

affected

Version	Status	Constraints
`10.0.26200.0`	affected	< 10.0.26200.8875

Microsoft

Windows 11 version 26H1

affected

Version	Status	Constraints
`10.0.28000.0`	affected	< 10.0.28000.2525

Microsoft

Windows Server 2012

affected

Version	Status	Constraints
`6.2.9200.0`	affected	< 6.2.9200.26226

Microsoft

Windows Server 2012 (Server Core installation)

affected

Version	Status	Constraints
`6.2.9200.0`	affected	< 6.2.9200.26226

Microsoft

Windows Server 2012 R2

affected

Version	Status	Constraints
`6.3.9600.0`	affected	< 6.3.9600.23291

Microsoft

Windows Server 2012 R2 (Server Core installation)

affected

Version	Status	Constraints
`6.3.9600.0`	affected	< 6.3.9600.23291

Microsoft

Windows Server 2016

affected

Version	Status	Constraints
`10.0.14393.0`	affected	< 10.0.14393.9339

Microsoft

Windows Server 2016 (Server Core installation)

affected

Version	Status	Constraints
`10.0.14393.0`	affected	< 10.0.14393.9339

Microsoft

Windows Server 2019

affected

Version	Status	Constraints
`10.0.17763.0`	affected	< 10.0.17763.9020

Microsoft

Windows Server 2019 (Server Core installation)

affected

Version	Status	Constraints
`10.0.17763.0`	affected	< 10.0.17763.9020

Microsoft

Windows Server 2022

affected

Version	Status	Constraints
`10.0.20348.0`	affected	< 10.0.20348.5386

Microsoft

Windows Server 2025

affected

Version	Status	Constraints
`10.0.26100.0`	affected	< 10.0.26100.33158

Microsoft

Windows Server 2025 (Server Core installation)

affected

Version	Status	Constraints
`10.0.26100.0`	affected	< 10.0.26100.33158

Configuration 1 [-]

OR	cpe:2.3:o:microsoft:windows_10_1607:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_1607:::::::x86:*
	cpe:2.3:o:microsoft:windows_10_1809:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_1809:::::::x86:*
	cpe:2.3:o:microsoft:windows_10_21h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_10_21h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_21h2:::::::x86:*
	cpe:2.3:o:microsoft:windows_10_22h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_10_22h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_22h2:::::::x86:*
	cpe:2.3:o:microsoft:windows_11_24h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_24h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_25h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_25h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_26h1:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_26h1:::::::arm64:*
	cpe:2.3:o:microsoft:windows_server_2012:-:::::::*
	cpe:2.3:o:microsoft:windows_server_2012:r2:::::::*
	cpe:2.3:o:microsoft:windows_server_2016::::::::
	cpe:2.3:o:microsoft:windows_server_2019::::::::
	cpe:2.3:o:microsoft:windows_server_2022::::::::
	cpe:2.3:o:microsoft:windows_server_2025::::::::

No data.

Vendor Product Versions

Microsoft

Windows 10 1607

Version	Status	Scheme	Platform
`[10.0.14393.0,10.0.14393.9339)`	affected	generic	['32-bit_systems', 'x64-based_systems']

Microsoft

Windows 10 1809

Version	Status	Scheme	Platform
`[10.0.17763.0,10.0.17763.9020)`	affected	generic	['32-bit_systems', 'x64-based_systems']

Microsoft

Windows 10 21h2

Version	Status	Scheme	Platform
`[10.0.19044.0,10.0.19044.7548)`	affected	generic	['32-bit_systems', 'arm64-based_systems', 'x64-based_systems']

Microsoft

Windows 10 22h2

Version	Status	Scheme	Platform
`[10.0.19045.0,10.0.19045.7548)`	affected	generic	['32-bit_systems', 'arm64-based_systems', 'x64-based_systems']

Microsoft

Windows 11 24h2

Version	Status	Scheme	Platform
`[10.0.26100.0,10.0.26100.8875)`	affected	generic	['arm64-based_systems', 'x64-based_systems']

Microsoft

Windows 11 25h2

Version	Status	Scheme	Platform
`[10.0.26200.0,10.0.26200.8875)`	affected	generic	['arm64-based_systems', 'x64-based_systems']

Microsoft

Windows 11 26h1

Version	Status	Scheme	Platform
`[10.0.28000.0,10.0.28000.2269)`	affected	generic	['arm64-based_systems', 'x64-based_systems']

Microsoft

Windows Server 2012

Version	Status	Scheme	Platform
`[6.2.9200.0,6.2.9200.26226)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2012 (server Core Installation)

Version	Status	Scheme	Platform
`[6.2.9200.0,6.2.9200.26226)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2012 R2

Version	Status	Scheme	Platform
`[6.3.9600.0,6.3.9600.23291)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2012 R2 (server Core Installation)

Version	Status	Scheme	Platform
`[6.3.9600.0,6.3.9600.23291)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2016

Version	Status	Scheme	Platform
`[10.0.14393.0,10.0.14393.9339)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2016 (server Core Installation)

Version	Status	Scheme	Platform
`[10.0.14393.0,10.0.14393.9339)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2019

Version	Status	Scheme	Platform
`[10.0.17763.0,10.0.17763.9020)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2019 (server Core Installation)

Version	Status	Scheme	Platform
`[10.0.17763.0,10.0.17763.9020)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2022

Version	Status	Scheme	Platform
`[10.0.20348.0,10.0.20348.5386)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2025

Version	Status	Scheme	Platform
`[10.0.26100.0,10.0.26100.33158)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2025 (server Core Installation)

Version	Status	Scheme	Platform
`[10.0.26100.0,10.0.26100.33158)`	affected	generic	['x64-based_systems']

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

Apply the latest cumulative updates from the Microsoft Security Update Guide that address CVE-2026-49177.
Enforce least privilege for local accounts and restrict the use of privileged accounts to reduce the risk of abuse by authorized users.
Monitor event logs and security telemetry for abnormal activity that might indicate attempts to read sensitive memory through the TCP/IP stack.

Generated by OpenCVE AI on July 31, 2026 at 09:40 UTC.

Tracking

Advisories

No advisories available

Metrics

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.443% probability within 30 days)

Exploitation none

Automatable no

Technical Impact partial

References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-49177
https://www.talosintelligence.com/vulnerability_reports/TALOS-2026-2427

History

Nov 11, 2026 1:30 AM First appearance in the feed. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Microsoft windows Server 2012 (server Core Installation) Microsoft windows Server 2012 R2 Microsoft windows Server 2012 R2 (server Core Installation) Microsoft windows Server 2016 (server Core Installation) Microsoft windows Server 2019 (server Core Installation) Microsoft windows Server 2025 (server Core Installation)
Vendors & Products		Microsoft windows Server 2012 (server Core Installation) Microsoft windows Server 2012 R2 Microsoft windows Server 2012 R2 (server Core Installation) Microsoft windows Server 2016 (server Core Installation) Microsoft windows Server 2019 (server Core Installation) Microsoft windows Server 2025 (server Core Installation)

Aug 12, 2026 6:30 PM Added references View changes

Type	Values Removed	Values Added
References		https://www.talosintelligence.com/vulnerability_reports/TALOS-2026-2427

Jul 16, 2026 4:30 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Jul 14, 2026 5:45 PM Description updated. Title updated. First appearance in the feed. Weaknesses updated. Affected versions updated. Affected vendors updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		Out-of-bounds read in Windows TCP/IP allows an authorized attacker to disclose information locally.
Title		Windows TCP/IP Information Disclosure Vulnerability
First Time appeared		Microsoft Microsoft windows 10 1607 Microsoft windows 10 1809 Microsoft windows 10 21h2 Microsoft windows 10 22h2 Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows 11 26h1 Microsoft windows Server 2012 Microsoft windows Server 2012 R2 Microsoft windows Server 2016 Microsoft windows Server 2019 Microsoft windows Server 2022 Microsoft windows Server 2025
Weaknesses		CWE-125
CPEs		cpe:2.3:o:microsoft:windows_10_1607:::::::x86:* cpe:2.3:o:microsoft:windows_10_1809:::::::x86:* cpe:2.3:o:microsoft:windows_10_21H2:::::::x86:* cpe:2.3:o:microsoft:windows_10_22H2:::::::x64:* cpe:2.3:o:microsoft:windows_11_24H2:::::::arm64:* cpe:2.3:o:microsoft:windows_11_25H2:::::::arm64:* cpe:2.3:o:microsoft:windows_11_26H1:::::::x64:* cpe:2.3:o:microsoft:windows_server_2012:::::::x64:* cpe:2.3:o:microsoft:windows_server_2012_R2:::::::x64:* cpe:2.3:o:microsoft:windows_server_2016:::::::: cpe:2.3:o:microsoft:windows_server_2019:::::::: cpe:2.3:o:microsoft:windows_server_2022:::::::: cpe:2.3:o:microsoft:windows_server_2025::::::::
Vendors & Products		Microsoft Microsoft windows 10 1607 Microsoft windows 10 1809 Microsoft windows 10 21h2 Microsoft windows 10 22h2 Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows 11 26h1 Microsoft windows Server 2012 Microsoft windows Server 2012 R2 Microsoft windows Server 2016 Microsoft windows Server 2019 Microsoft windows Server 2022 Microsoft windows Server 2025
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-49177
Metrics		cvssV3_1 `{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C'}`

Subscriptions

Microsoft Windows 10 1607 Windows 10 1809 Windows 10 21h2 Windows 10 21h2 Windows 10 22h2 Windows 10 22h2 Windows 11 24h2 Windows 11 24h2 Windows 11 25h2 Windows 11 25h2 Windows 11 26h1 Windows 11 26h1 Windows Server 2012 Windows Server 2012 (server Core Installation) Windows Server 2012 R2 Windows Server 2012 R2 Windows Server 2012 R2 (server Core Installation) Windows Server 2016 Windows Server 2016 (server Core Installation) Windows Server 2019 Windows Server 2019 (server Core Installation) Windows Server 2022 Windows Server 2025 Windows Server 2025 (server Core Installation)

Weaknesses