Patch Tuesday

Patch Tuesday April 2026 – known issues, zero-days and what to do

On 14 Apr 2026 Microsoft fixed 181 vulnerabilities – critical: 23, already exploited (zero-days): 2. Known issues with the updates: 2 with workaround, 1 fixed.

181vulnerabilities

23critical

2zero-days

3known issues

What to do now

Zero-days first: 2 vulnerabilities are already being exploited (CVE-2026-32201, CVE-2026-32202) – install the updates as soon as possible, starting with servers and exposed systems.
23 critical vulnerabilities (mainly Windows, Azure, Microsoft Office) – roll out promptly after a short test.
Known issue with KB5083769: “Windows 11: Universal Print printers from Windows 10 fail after KB5083769 or later” – a workaround is available.
Known issue with KB5126934, KB5126967: “SQL Server: access violation querying sys.dm_exec_requests during database recovery” – a workaround is available.
The issue “SQL Server: linked server MSDASQL queries with provider string fail with error 7416” with KB5126934, KB5126967, KB5128492 has been fixed (with October 2026 GDR update).
Taking effect on 14 Apr 2026: “Windows Server: Kerberos KDC defaults to AES, RC4 service tickets blocked (CVE-2026-20833)” – check in good time.

Zero-days: already exploited

CVE-2026-32201ImportantCVSS 6.5Spoofing

Microsoft SharePoint Server Spoofing Vulnerability

Microsoft Office · KB5002861 KB5002854 KB5002853

CVE-2026-32202ImportantCVSS 4.3Spoofing

Windows Shell Spoofing Vulnerability

Windows, Windows ESU (Extended Security Updates) · KB5099538 KB5099540 KB5099539 KB5099536

Critical vulnerabilities (23)

CVE-2026-32186CriticalCVSS 10.0Elevation of privilege

Microsoft Bing Elevation of Privilege Vulnerability

Apps

CVE-2026-32213CriticalCVSS 10.0Elevation of privilege

Azure AI Foundry Elevation of Privilege Vulnerability

Azure

CVE-2026-33105CriticalCVSS 10.0Elevation of privilege

Microsoft Azure Kubernetes Service Elevation of Privilege Vulnerability

Azure

CVE-2026-33107CriticalCVSS 10.0Elevation of privilege

Azure Databricks Elevation of Privilege Vulnerability

Azure

CVE-2026-33819CriticalCVSS 10.0Remote code execution

Microsoft Bing Remote Code Execution Vulnerability

Apps

CVE-2026-35431CriticalCVSS 10.0Spoofing

Microsoft Entra ID Entitlement Management Spoofing Vulnerability

Azure

Show 17 more critical vulnerabilities

CVE-2026-21515CriticalCVSS 9.9Elevation of privilege

Azure IoT Central Elevation of Privilege Vulnerability

Azure

CVE-2026-33824CriticalCVSS 9.8Remote code execution

Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability

Windows, Windows ESU (Extended Security Updates) · KB5082123 KB5082142 KB5082200 KB5082063

CVE-2026-24303CriticalCVSS 9.6Elevation of privilege

Microsoft Partner Center Elevation of Privilege Vulnerability

Azure

CVE-2026-26135CriticalCVSS 9.6Elevation of privilege

Azure Custom Locations Resource Provider (RP) Elevation of Privilege Vulnerability

Azure

CVE-2026-32210CriticalCVSS 9.3Spoofing

Microsoft Dynamics 365 (online) Spoofing Vulnerability

Microsoft Dynamics

CVE-2026-33102CriticalCVSS 9.3Elevation of privilege

Microsoft 365 Copilot Elevation of Privilege Vulnerability

Apps

CVE-2026-32211CriticalCVSS 9.1Information disclosure

Azure MCP Server Information Disclosure Vulnerability

Azure

CVE-2026-32157CriticalCVSS 8.8Remote code execution

Remote Desktop Client Remote Code Execution Vulnerability

Windows · KB5083768

CVE-2026-26150CriticalCVSS 8.6Elevation of privilege

Microsoft Purview eDiscovery Elevation of Privilege Vulnerability

Azure

CVE-2026-32173CriticalCVSS 8.6Information disclosure

Azure SRE Agent Information Disclosure Vulnerability

Azure

CVE-2026-32190CriticalCVSS 8.4Remote code execution

Microsoft Office Remote Code Execution Vulnerability

Microsoft Office · KB5002859

CVE-2026-33114CriticalCVSS 8.4Remote code execution

Microsoft Word Remote Code Execution Vulnerability

Microsoft Office

CVE-2026-33115CriticalCVSS 8.4Remote code execution

Microsoft Word Remote Code Execution Vulnerability

Microsoft Office

CVE-2026-33827CriticalCVSS 8.1Remote code execution

Windows TCP/IP Remote Code Execution Vulnerability

Windows, Windows ESU (Extended Security Updates) · KB5082123 KB5082142 KB5082200 KB5082063

CVE-2026-32172CriticalCVSS 8.0Remote code execution

Microsoft Power Apps Remote Code Execution Vulnerability

Microsoft Dynamics

CVE-2026-33826CriticalCVSS 8.0Remote code execution

Windows Active Directory Remote Code Execution Vulnerability

Windows, Windows ESU (Extended Security Updates) · KB5082123 KB5082142 KB5082063 KB5082060

CVE-2026-23666CriticalCVSS 7.5Denial of service

.NET Framework Denial of Service Vulnerability

Developer tools (.NET, Visual Studio …) · KB5082411 KB5082403 KB5082404 KB5082414

Updates (KB) of this month

KB numbers according to the Security Update Guide; known issues from our update issues – click a KB to see all its entries.

Update	Product family	Vulnerabilities	Known issues
KB5126934	SQL Server	1	2
KB5126967	SQL Server	1	2
KB5083769	Windows	116	1
KB5128492	SQL Server	1	1
KB5082063	Windows	119	none known
KB5082142	Windows	112	none known
KB5082123	Windows	103	none known
KB5082200	Windows	103	none known
KB5083768	Windows	72	none known
KB5082052	Windows	61	none known
KB5082060	Windows	23	none known
KB5082198	Windows	8	none known

Show 38 more updates

Update	Product family	Vulnerabilities	Known issues
KB5002855	Microsoft Office	5	none known
KB5002860	Microsoft Office	5	none known
KB5082127	Windows	4	none known
KB5086095	Developer tools (.NET, Visual Studio …)	4	none known
KB5086096	Developer tools (.NET, Visual Studio …)	4	none known
KB5086097	Developer tools (.NET, Visual Studio …)	4	none known
KB5082411	Developer tools (.NET, Visual Studio …)	3	none known
KB5082403	Developer tools (.NET, Visual Studio …)	3	none known
KB5082414	Developer tools (.NET, Visual Studio …)	3	none known
KB5082404	Developer tools (.NET, Visual Studio …)	2	none known
KB5082426	Developer tools (.NET, Visual Studio …)	2	none known
KB5082126	Windows	2	none known
KB5002861	Microsoft Office	2	none known
KB5002854	Microsoft Office	2	none known
KB5002853	Microsoft Office	2	none known
KB5083245	SQL Server	2	none known
KB5082427	Developer tools (.NET, Visual Studio …)	1	none known
KB5002859	Microsoft Office	1	none known
KB5002862	Microsoft Office	1	none known
KB5002856	Microsoft Office	1	none known
KB5083252	SQL Server	1	none known
KB5084819	SQL Server	1	none known
KB5084817	SQL Server	1	none known
KB5084821	SQL Server	1	none known
KB5084820	SQL Server	1	none known
KB5128496	SQL Server	1	none known
KB5084814	SQL Server	1	none known
KB5002808	Microsoft Office	1	none known
KB5099538	Windows	1	none known
KB5099540	Windows	1	none known
KB5099539	Windows	1	none known
KB5099536	Windows	1	none known
KB5101650	Windows	1	none known
KB5099414	Windows	1	none known
KB5082424	Developer tools (.NET, Visual Studio …)	1	none known
KB5078943	Microsoft Dynamics	1	none known
KB5084815	SQL Server	1	none known
KB5091596	Developer tools (.NET, Visual Studio …)	1	none known

Known issues with the updates

WorkaroundKnown issueCommunity reportCheck scriptUpdated 2 Nov 2026

Windows 11: Universal Print printers from Windows 10 fail after KB5083769 or later

Universal Print printers that were first installed on Windows 10 reportedly stop working after Windows 11 KB5083769 or a later update. News reports say Microsoft confirmed the issue, but no vendor source is available to us, so this is treated as reported by users and media, not yet confirmed by the vendor. No fix is reported; re-adding the printer is the reported workaround.

Microsoft · Windows 11 (KB5083769 and later; 26H2 reportedly also affected)

WorkaroundKnown issueUpdated 1 Nov 2026

SQL Server: access violation querying sys.dm_exec_requests during database recovery

Queries against sys.dm_exec_requests can raise an access violation and generate a dump file while a database is still recovering. Microsoft confirms the issue for SQL Server 2025 and 2022 updates and is investigating a fix. Mitigations are available.

Microsoft · SQL Server

FixedKnown issueUpdated 1 Nov 2026

SQL Server: linked server MSDASQL queries with provider string fail with error 7416

Linked server queries that use the MSDASQL provider (OLE DB Provider for ODBC Drivers) and specify a provider string ([user]) fail with error 7416 for users who are not sysadmin. A stricter connection validation check in the Database Engine causes this. Microsoft confirms the issue and states it is addressed starting with the October 2026 GDR update.

Microsoft · SQL Server

Dated changes this month

In effectDated change14 Apr 2026

Windows Server: Kerberos KDC defaults to AES, RC4 service tickets blocked (CVE-2026-20833)

Microsoft is hardening the Kerberos Key Distribution Center (KDC) on domain controllers against CVE-2026-20833, an information disclosure flaw that lets attackers obtain RC4-encrypted service tickets for offline password attacks. Since the updates of 14 April 2026, the default for accounts without an explicit encryption setting is AES-SHA1 only. Updates from July 2026 remove the rollback option. Status as of 2026-11-01: the change is live.

Microsoft · Windows Server

By product family

Windows131
Azure15
Microsoft Office14
Developer tools (.NET, Visual Studio …)9
SQL Server3
Microsoft Dynamics3
Apps3
Browser (Edge)2

More about this month

Where the information comes from

Fixed vulnerabilities, severity, zero-days and KB numbers come from the official Microsoft Security Update Guide (MSRC); known issues, workarounds and dated changes from our update issues, each with its source. “What to do now” is derived from this data using fixed rules, without AI.

Affected? We can help.

We check whether your systems are affected, apply workarounds properly and plan for dated changes in good time.

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