Vendor advisories

Microsoft Security Response Center

Browse 17,484 advisories from this official source. Search by product, CVE, severity, or advisory ID.

Current Checked 4 hours ago Checked every 6 hours

17,484 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.

RSS for these results
Microsoft Security Response CenterCVE-2026-55120
CriticalCVSS 7.8

Microsoft PowerPoint Remote Code Execution Vulnerability

Heap-based buffer overflow in Microsoft Office PowerPoint 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, 16.111.26071215, 16.0.5561.1000
Vendor guidance

Click to Run Release Notes Install KB5002867.

Microsoft Security Response CenterCVE-2026-55056
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 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, 16.111.26071215, 16.0.5561.1000
Vendor guidance

Click to Run Release Notes Install KB5002887.

Microsoft Security Response CenterCVE-2026-55049
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 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, 16.111.26071215, 16.0.5561.1000
Vendor guidance

Click to Run Release Notes Install KB5002748.

Microsoft Security Response CenterCVE-2026-55045
CriticalCVSS 8.4

Microsoft Office Remote Code Execution Vulnerability

Out-of-bounds read in Microsoft Office allows an unauthorized attacker to execute code locally.

Affected productsMicrosoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019, Microsoft Office 2019 for 32-bit editions, Microsoft Office 2019 for 64-bit editions
Fixed versions16.0.5561.1001, 16.0.10417.20175, https://aka.ms/OfficeSecurityReleases, 16.111.26071215
Vendor guidance

Click to Run Release Notes Install KB5002891. Install KB5002892. Install KB5002883. Install KB5002885. Install KB5002882. Install KB5002887.

Microsoft Security Response CenterCVE-2026-55040
CriticalCVSS 9.1

Microsoft SharePoint Server Security Feature Bypass Vulnerability

Weak authentication in Microsoft Office SharePoint allows an unauthorized attacker to bypass a security feature over a network.

Affected productsMicrosoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019, Microsoft SharePoint Server Subscription Edition
Fixed versions16.0.5561.1001, 16.0.10417.20175, 16.0.19725.20434
Vendor guidance

Install KB5002891. Install KB5002883. Install KB5002882.

Microsoft Security Response CenterCVE-2026-55033
CriticalCVSS 7.8

Microsoft Word Remote Code Execution Vulnerability

Integer overflow or wraparound in Microsoft Office Word allows an unauthorized attacker to execute code locally.

Affected productsMicrosoft SharePoint Server 2019, Microsoft Office 2019 for 32-bit editions, Microsoft Office 2019 for 64-bit editions, Microsoft 365 Apps for Enterprise for 32-bit Systems
Fixed versions16.0.10417.20175, https://aka.ms/OfficeSecurityReleases, 16.111.26071215, 16.0.5561.1000
Vendor guidance

Click to Run Release Notes Install KB5002883. Install KB5002885. Install KB5002890. Install KB5002891. Install KB5002892. Install KB5002882.

Microsoft Security Response CenterCVE-2026-55022
CriticalCVSS 7.8

Microsoft Office Remote Code Execution Vulnerability

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

Affected productsMicrosoft Office 365 for Mac, Microsoft Office 2019 for 32-bit editions, Microsoft Office 2019 for 64-bit editions, Microsoft 365 Apps for Enterprise for 32-bit Systems
Fixed versions16.111.26071215, https://aka.ms/OfficeSecurityReleases, 16.0.5561.1000
Vendor guidance

Release Notes Click to Run Install KB5002887.

Microsoft Security Response CenterCVE-2026-55018
CriticalCVSS 7.8

Microsoft Office Remote Code Execution Vulnerability

Use after free in Microsoft Office allows an unauthorized attacker to execute code locally.

Affected productsMicrosoft Office 365 for Mac, Microsoft Office 2019 for 32-bit editions, Microsoft Office 2019 for 64-bit editions, Microsoft 365 Apps for Enterprise for 32-bit Systems
Fixed versions16.111.26071215, https://aka.ms/OfficeSecurityReleases, 16.0.5561.1000
Vendor guidance

Release Notes Click to Run Install KB5002887.

Microsoft Security Response CenterCVE-2026-55008
CriticalCVSS 9.6

Microsoft Exchange Server Spoofing Vulnerability

Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.

Affected productsMicrosoft Exchange Server 2016 Cumulative Update 23, Microsoft Exchange Server 2019 Cumulative Update 14, Microsoft Exchange Server 2019 Cumulative Update 15, Microsoft Exchange Server Subscription Edition RTM
Fixed versions15.01.2507.071, 15.02.1544.043, 15.02.1748.048, 15.02.2562.045
Vendor guidance

Install KB5103215. Install KB5103214. Install KB5103213. Install KB5103212.

Microsoft Security Response CenterCVE-2026-54999
CriticalCVSS 8.8

Windows TCP/IP Remote Code Execution Vulnerability

Concurrent execution using shared resource with improper synchronization ('race condition') in Windows TCP/IP allows an unauthorized attacker to execute code over an adjacent network.

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 versions10.0.17763.9020, 10.0.20348.5386, 10.0.19044.7548, 10.0.19045.7548
Vendor guidance

Install KB5099538. Install KB5099540. Install KB5099539. Install KB5099536. Install KB5101650. Install KB5101649. Install KB5099535. Install KB5099445. Install KB5099444.

Microsoft Security Response CenterCVE-2026-54995
CriticalCVSS 8.1

Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability

Use after free in Reliable Multicast Transport Driver (RMCAST) allows an unauthorized attacker to execute code over a network.

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 versions10.0.17763.9020, 10.0.20348.5386, 10.0.19044.7548, 10.0.19045.7548
Vendor guidance

Install KB5099538. Install KB5099540. Install KB5099539. Install KB5099536. Install KB5101650. Install KB5101649. Install KB5099535. Install KB5099445. Install KB5099444.

Microsoft Security Response CenterCVE-2026-54992
CriticalCVSS 8.4

Microsoft Message Queuing Queue Manager Remote Code Execution Vulnerability

Heap-based buffer overflow in Windows Message Queuing Queue Manager 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 versions10.0.17763.9020, 10.0.20348.5386, 10.0.19044.7548, 10.0.19045.7548
Vendor guidance

Install KB5099538. Install KB5099540. Install KB5099539. Install KB5099536. Install KB5101650. Install KB5101649. Install KB5099535. Install KB5099445. Install KB5099444.

Microsoft Security Response CenterCVE-2026-54982
CriticalCVSS 8.8

Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability

Integer underflow (wrap or wraparound) in Reliable Multicast Transport Driver (RMCAST) allows an unauthorized attacker to execute code over an adjacent network.

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 versions10.0.17763.9020, 10.0.20348.5386, 10.0.19044.7548, 10.0.19045.7548
Vendor guidance

Install KB5099538. Install KB5099540. Install KB5099539. Install KB5099536. Install KB5101650. Install KB5101649. Install KB5099535. Install KB5099445. Install KB5099444.

Microsoft Security Response CenterCVE-2026-54127
CriticalCVSS 7.4

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 2025 (Server Core installation), Windows 11 Version 25H2 for ARM64-based Systems, Windows 11 Version 25H2 for x64-based Systems
Fixed versions10.0.20348.5386, 10.0.26100.33158, 10.0.26200.8875, 10.0.26100.8875
Vendor guidance

Install KB5099540. Install KB5099536. Install KB5101650. Install KB5101649.

Microsoft Security Response CenterCVE-2026-54121
CriticalCVSS 8.8

Active Directory Certificate Services Elevation of Privilege Vulnerability

Improper authorization in Active Directory Certificate Services (AD CS) allows an authorized attacker to elevate privileges over a network.

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 versions10.0.17763.9020, 10.0.20348.5386, 10.0.26100.33158, 10.0.14393.9339
Vendor guidance

Install KB5099538. Install KB5099540. Install KB5099536. Install KB5099535. Install KB5099445. Install KB5099444.

Microsoft Security Response CenterCVE-2026-50694
CriticalCVSS 8.1

Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution Vulnerability

Use after free in Windows Secure Socket Tunneling Protocol (SSTP) allows an unauthorized attacker to execute code over a network.

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 versions10.0.17763.9020, 10.0.20348.5386, 10.0.19044.7548, 10.0.19045.7548
Vendor guidance

Install KB5099538. Install KB5099540. Install KB5099539. Install KB5099536. Install KB5101650. Install KB5101649. Install KB5099535. Install KB5099445. Install KB5099444.

Microsoft Security Response CenterCVE-2026-50680
CriticalCVSS 8.2

Windows Hyper-V Elevation of Privilege Vulnerability

Heap-based buffer overflow in Windows Hyper-V allows an authorized attacker to elevate privileges 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 versions10.0.17763.9020, 10.0.20348.5386, 10.0.19044.7548, 10.0.19045.7548
Vendor guidance

Install KB5099538. Install KB5099540. Install KB5099539. Install KB5099536. Install KB5101650. Install KB5101649.

Microsoft Security Response CenterCVE-2026-50522
CriticalCVSS 9.8

Microsoft SharePoint Remote Code Execution Vulnerability

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

Affected productsMicrosoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019, Microsoft SharePoint Server Subscription Edition
Fixed versions16.0.5561.1001, 16.0.10417.20175, 16.0.19725.20434
Vendor guidance

Install KB5002891. Install KB5002883. Install KB5002882.

Microsoft Security Response CenterCVE-2026-50518
CriticalCVSS 9.8

Windows DHCP Server Remote Code Execution Vulnerability

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

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 versions10.0.17763.9020, 10.0.20348.5386, 10.0.26100.33158, 10.0.14393.9339
Vendor guidance

Install KB5099538. Install KB5099540. Install KB5099536. Install KB5099535. Install KB5099445. Install KB5099444.

Microsoft Security Response CenterCVE-2026-50474
CriticalCVSS 8.8

Remote Desktop Client Remote Code Execution Vulnerability

Use after free in Remote Desktop Client allows an unauthorized attacker to execute code over a network.

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 versions10.0.17763.9020, 10.0.20348.5386, 10.0.19044.7548, 10.0.19045.7548
Vendor guidance

Install KB5099538. Install KB5099540. Install KB5099539. Install KB5099536. Install KB5101650. Install KB5101649. Install KB5099535. Install KB5099445. Install KB5099444.

Microsoft Security Response CenterCVE-2026-50467
CriticalCVSS 7.8

Microsoft Office Remote Code Execution Vulnerability

Use after free 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, 16.111.26071215, 16.0.5561.1000
Vendor guidance

Click to Run Release Notes Install KB5002887.

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.

How we check our sources