Vendor advisories

Microsoft Security Response Center

Browse 17,903 advisories from this official source. Search by product, CVE, severity, or advisory ID.

Current Checked 3 hours ago Checked every 6 hours

17,903 advisories

Each date says whether the vendor published or updated the bulletin. A vendor bulletin describes products that may be affected. It does not prove that the vulnerable product or version is installed in your environment.

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Microsoft Security Response CenterCVE-2026-42831
CriticalCVSS 7.8

Microsoft Office Remote Code Execution Vulnerability

Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.

Affected productsMicrosoft Office LTSC for Mac 2021, Microsoft Office for Android, Microsoft Office LTSC for Mac 2024
Fixed versions16.109.26051019, 16.0.19822.20190
Vendor guidance

Release Notes

Microsoft Security Response CenterCVE-2026-41103
CriticalCVSS 9.1

Microsoft SSO Plugin for Jira & Confluence Elevation of Privilege Vulnerability

Incorrect implementation of authentication algorithm in Microsoft SSO Plugin for Jira & Confluence allows an unauthorized attacker to elevate privileges over a network.

Affected productsMicrosoft JIRA SAML SSO plugin, Microsoft Confluence SAML SSO plugin
Fixed versions1.3.3, 7.4.0
Vendor guidance

Release Notes

Microsoft Security Response CenterCVE-2026-41096
CriticalCVSS 9.8

Windows DNS Client Remote Code Execution Vulnerability

Heap-based buffer overflow in Microsoft Windows DNS allows an unauthorized attacker to execute code over a network.

Affected productsWindows Server 2025 (Server Core installation), Windows 11 Version 25H2 for ARM64-based Systems, Windows 11 Version 25H2 for x64-based Systems, Windows 11 Version 23H2 for ARM64-based Systems
Fixed versions10.0.26100.32860, 10.0.26100.32772, 10.0.26200.8457, 10.0.26200.8390
Vendor guidance

Install KB5087539. Install KB5087423. Install KB5089549. Install KB5089466. Install KB5087420. Install KB5093998. Install KB5087541. Install KB5089548.

Microsoft Security Response CenterCVE-2026-41089
CriticalCVSS 9.8

Windows Netlogon Remote Code Execution Vulnerability

Stack-based buffer overflow in Windows Netlogon allows an unauthorized attacker to execute code over a network.

Affected productsWindows Server 2019, Windows Server 2019 (Server Core installation), Windows Server 2022, Windows Server 2022 (Server Core installation)
Fixed versions10.0.17763.8755, 10.0.20348.5139, 10.0.20348.5074, 10.0.26100.32860
Vendor guidance

Install KB5087538. Install KB5087545. Install KB5087424. Install KB5087539. Install KB5087423. Install KB5087541. Install KB5087537. Install KB5087470. Install KB5087471.

Microsoft Security Response CenterCVE-2026-40403
CriticalCVSS 8.8

Windows Graphics Component Remote Code Execution Vulnerability

Heap-based buffer overflow in Windows Win32K - GRFX allows an authorized attacker to execute code locally.

Affected productsWindows 10 Version 1809 for 32-bit Systems, Windows 10 Version 1809 for x64-based Systems, Windows Server 2019, Windows Server 2019 (Server Core installation)
Fixed versions10.0.17763.8755, 10.0.20348.5139, 10.0.20348.5074, 10.0.19044.7291
Vendor guidance

Install KB5087538. Install KB5087545. Install KB5087424. Install KB5087544. Install KB5094127. Install KB5087539. Install KB5087423. Install KB5089549. Install KB5089466. Install KB5087420. Install KB5093998. Install ...

Microsoft Security Response CenterCVE-2026-40402
CriticalCVSS 9.3

Windows Hyper-V Elevation of Privilege Vulnerability

Use after free in Windows Hyper-V allows an unauthorized attacker to elevate privileges locally.

Affected productsWindows Server 2022, Windows Server 2022 (Server Core installation), Windows 11 Version 23H2 for ARM64-based Systems, Windows 11 Version 23H2 for x64-based Systems
Fixed versions10.0.20348.5139, 10.0.20348.5074, 10.0.22631.7079, 10.0.22631.7219
Vendor guidance

Install KB5087545. Install KB5087424. Install KB5087420. Install KB5093998.

Microsoft Security Response CenterCVE-2026-40366
CriticalCVSS 8.4

Microsoft Word Remote Code Execution Vulnerability

Access of resource using incompatible type ('type confusion') in Microsoft Office Word allows an unauthorized attacker to execute code locally.

Affected productsMicrosoft Office 2019 for 32-bit editions, Microsoft Office 2019 for 64-bit editions, Microsoft 365 Apps for Enterprise for 32-bit Systems, Microsoft 365 Apps for Enterprise for 64-bit Systems
Fixed versionshttps://aka.ms/OfficeSecurityReleases, 16.109.26051019, 16.0.5552.1000
Vendor guidance

Click to Run Release Notes Install KB5002858.

Microsoft Security Response CenterCVE-2026-40365
CriticalCVSS 8.8

Microsoft SharePoint Server Remote Code Execution Vulnerability

Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.

Affected productsMicrosoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019, Microsoft SharePoint Server Subscription Edition
Fixed versions16.0.5552.1002, 16.0.10417.20128, 16.0.19725.20280
Vendor guidance

Install KB5002868. Install KB5002870. Install KB5002863.

Microsoft Security Response CenterCVE-2026-40364
CriticalCVSS 8.4

Microsoft Word Remote Code Execution Vulnerability

Access of resource using incompatible type ('type confusion') in Microsoft Office Word allows an unauthorized attacker to execute code locally.

Affected productsMicrosoft Office 2019 for 32-bit editions, Microsoft Office 2019 for 64-bit editions, Microsoft 365 Apps for Enterprise for 32-bit Systems, Microsoft 365 Apps for Enterprise for 64-bit Systems
Fixed versionshttps://aka.ms/OfficeSecurityReleases, 16.109.26051019, 16.0.5552.1000
Vendor guidance

Click to Run Release Notes Install KB5002858.

Microsoft Security Response CenterCVE-2026-40363
CriticalCVSS 8.4

Microsoft Office Remote Code Execution Vulnerability

Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.

Affected productsMicrosoft Office 2019 for 32-bit editions, Microsoft Office 2019 for 64-bit editions, Microsoft 365 Apps for Enterprise for 32-bit Systems, Microsoft 365 Apps for Enterprise for 64-bit Systems
Fixed versionshttps://aka.ms/OfficeSecurityReleases, 16.109.26051019, 16.0.5552.1000, 16.0.19822.20190
Vendor guidance

Click to Run Release Notes Install KB5002866.

Microsoft Security Response CenterCVE-2026-40358
CriticalCVSS 8.4

Microsoft Office Remote Code Execution Vulnerability

Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.

Affected productsMicrosoft Office 2019 for 32-bit editions, Microsoft Office 2019 for 64-bit editions, Microsoft 365 Apps for Enterprise for 32-bit Systems, Microsoft 365 Apps for Enterprise for 64-bit Systems
Fixed versionshttps://aka.ms/OfficeSecurityReleases, 16.109.26051019, 16.0.5552.1000
Vendor guidance

Click to Run Release Notes Install KB5002866.

Microsoft Security Response CenterCVE-2026-35421
CriticalCVSS 7.8

Windows GDI Remote Code Execution Vulnerability

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

Affected productsWindows 10 Version 1809 for 32-bit Systems, Windows 10 Version 1809 for x64-based Systems, Windows Server 2019, Windows Server 2019 (Server Core installation)
Fixed versions10.0.17763.8755, 10.0.20348.5139, 10.0.20348.5074, 10.0.19044.7291
Vendor guidance

Install KB5087538. Install KB5087545. Install KB5087424. Install KB5087544. Install KB5094127. Install KB5087539. Install KB5087423. Install KB5089549. Install KB5089466. Install KB5087420. Install KB5093998. Install ...

Microsoft Security Response CenterCVE-2026-20823
HighCVSS 5.5

Windows File Explorer Information Disclosure Vulnerability

Exposure of sensitive information to an unauthorized actor in Windows File Explorer allows an authorized attacker to disclose information locally.

Affected productsWindows 10 Version 1809 for 32-bit Systems, Windows 10 Version 1809 for x64-based Systems, Windows Server 2019, Windows Server 2019 (Server Core installation)
Fixed versions10.0.17763.8276, 10.0.20348.4648, 10.0.19044.6809, 10.0.19045.6809
Vendor guidance

Install KB5073723. Install KB5073457. Install KB5073724. Install KB5073379. Install KB5074109. Install KB5073455. Install KB5073450. Install KB5073722.

Microsoft Security Response CenterCVE-2026-42899
HighCVSS 7.5

ASP.NET Core Denial of Service Vulnerability

Loop with unreachable exit condition ('infinite loop') in ASP.NET Core allows an unauthorized attacker to deny service over a network.

Affected products.NET 8.0 installed on Windows, .NET 9.0 installed on Linux, .NET 8.0 installed on Mac OS, .NET 8.0 installed on Linux
Fixed versions8.0.27, 9.0.16, 10.0.8
Vendor guidance

Install KB5093447. Install KB5093448. Install KB5093446.

Microsoft Security Response CenterCVE-2026-42896
HighCVSS 7.8

Windows DWM Core Library Elevation of Privilege Vulnerability

Integer overflow or wraparound in Windows DWM Core Library allows an authorized attacker to elevate privileges locally.

Affected productsWindows Server 2025 (Server Core installation), Windows 11 Version 25H2 for ARM64-based Systems, Windows 11 Version 25H2 for x64-based Systems, Windows 11 Version 24H2 for ARM64-based Systems
Fixed versions10.0.26100.32860, 10.0.26100.32772, 10.0.26200.8457, 10.0.26200.8390
Vendor guidance

Install KB5087539. Install KB5087423. Install KB5089549. Install KB5089466. Install KB5089548.

Microsoft Security Response CenterCVE-2026-42893
HighCVSS 7.4

Microsoft Outlook for iOS Tampering Vulnerability

Improper neutralization of special elements used in a command ('command injection') in M365 Copilot allows an unauthorized attacker to perform tampering over a network.

Affected productsMicrosoft Outlook for iOS
Fixed versions5.2617.1
Vendor guidance

See the Microsoft Security Update Guide for the update that applies to your product.

Microsoft Security Response CenterCVE-2026-42832
HighCVSS 7.7

Microsoft Office Spoofing Vulnerability

Improper access control in Microsoft Office allows an unauthorized attacker to perform spoofing locally.

Affected productsMicrosoft Word for Android, Microsoft Excel for Android, Microsoft Office LTSC for Mac 2021, Microsoft Office LTSC for Mac 2024
Fixed versions16.0.19822.20190, 16.109.26051019
Vendor guidance

Release Notes

Before you act

Start with the vendor's bulletin.

We normalize the fields that vendors publish so you can search and compare advisories in one place. We do not replace the original bulletin or turn a product-name match into proof that a system is vulnerable.

Confirm the installed product and version, read the linked vendor guidance, and test the recommended update or mitigation through your normal change process.

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