A critical heap-based buffer overflow in the Microsoft Remote Desktop Client could allow remote code execution if a user initiates a connection to an attacker-controlled server.

The vulnerability consists of a heap-based buffer overflow within the Remote Desktop Client. It requires an attacker to host a malicious RDP server and successfully lure a victim into establishing a connection.

The exploitation of this flaw could grant an attacker full control over the user’s workstation, leading to the exfiltration of sensitive data and potential unauthorized access to the broader corporate network. The CVSS score of 8.8 highlights the high severity and the necessity for immediate patch management to mitigate the risk of system compromise.

Immediate Action: Deploy the Microsoft June 2026 security update (KB5094127) to all endpoints using the Remote Desktop Client.

Proactive Monitoring: Audit network logs for connections to unauthorized or anomalous RDP endpoints.

Compensating Controls: Implement network-level egress filtering to prevent workstations from initiating RDP connections to untrusted external IP addresses.

Public Exploit Available: false

Organizations should treat this vulnerability with high urgency. Patching the Remote Desktop Client via the referenced KB is the most effective way to eliminate this attack vector and protect user workstations from malicious RDP-based exploitation.