Microsoft warns April updates can misrender Remote Desktop security prompts
Summary
Microsoft says April 2026 updates can cause Remote Desktop security warnings to overlap or show misplaced or hidden buttons on multi-monitor systems with different display scaling, making prompts harder to review or use.
Key points
- Microsoft confirmed the issue affects supported Windows versions, including Windows 11, Windows 10, and Windows Server.
- The problem can occur on multi-monitor systems with differing display scaling, causing overlapping warning text and misplaced or partially hidden buttons.
- The affected prompts appear when opening RDP files and show publisher information, the remote address, and local resource redirections before a connection.
- Unsigned RDP files are labeled “Caution: Unknown remote connection”; signed files display their publisher for user verification.
- Microsoft introduced the prompts in April 2026 updates as protections against malicious RDP connection files.
- The article says APT29 has previously used RDP files in phishing campaigns to steal credentials and documents.
Article Details
- Event Type
- Microsoft-confirmed display issue affecting Remote Desktop security warning dialogs after April 2026 cumulative updates.
- Impact
- On systems with multiple monitors using different display scaling settings, warning text may overlap and buttons may be hidden or misplaced, making the prompts difficult or impossible to read and use. The issue affects supported Windows versions, including Windows 11, Windows 10, and Windows Server.
Threat Actors
Vendors
Products
Microsoft WindowsMicrosoft confirmed that April 2026 cumulative updates introduced a known issue causing Remote Desktop (.rdp) security warning dialogs to display incorrectly on supported Windows versions.Remote DesktopMicrosoft confirmed that April 2026 cumulative updates introduced a known issue causing Remote Desktop (.rdp) security warning dialogs to display incorrectly on supported Windows versions.