Microsoft Releases Critical Security Update for CVE-2025-65046

Microsoft has released an emergency security update to address CVE-2025-65046, a critical vulnerability affecting Windows operating systems. The flaw, which received a CVSS score of 9.8 out of 10, could allow remote code execution without user interaction.

The vulnerability impacts Windows 10 version 1809 through 22H2, Windows 11 versions 21H2 and 22H2, and Windows Server 2019 and 2022. Microsoft rates this as a "Critical" severity issue requiring immediate attention.

Technical Details

The vulnerability exists in the Windows Remote Desktop Protocol (RDP) service, specifically in how it handles certain malformed packets. Attackers could exploit this remotely without authentication, potentially gaining system-level privileges on unpatched systems.

Affected Products

• Windows 10 (1809, 1903, 1909, 2004, 20H2, 21H1, 21H2, 22H2)
• Windows 11 (21H2, 22H2)
• Windows Server 2019
• Windows Server 2022

Mitigation Steps

1. Enable automatic updates or manually check for updates immediately
2. Apply the latest security patches from Windows Update
3. For enterprise environments, deploy patches through WSUS or Microsoft Endpoint Manager
4. Consider temporarily disabling RDP services if immediate patching isn't possible

Timeline

Microsoft became aware of the vulnerability on March 15, 2025, after reports of active exploitation in the wild. The company developed and released patches within 72 hours, demonstrating the severity of the threat.

Additional Resources

• Microsoft Security Update Guide
• CVE-2025-65046 Details
• Microsoft Advisory KB5099123

Security researchers recommend organizations prioritize this update above all others, as threat actors are actively developing exploits for this vulnerability. Microsoft has not disclosed specific details about the attacks but confirms they observed attempts to compromise systems before the patch release.

For organizations unable to patch immediately, Microsoft recommends implementing network segmentation and monitoring RDP traffic for suspicious patterns until updates can be applied.