CVE-2026-69518 – Windows Remote Desktop Remote Code Execution Vulnerability

CVE-2026-69518 is a critical heap-based buffer overflow vulnerability in Windows Remote Desktop. An unauthorized attacker could join a Remote Desktop sharing session and send specially crafted clipboard data to the sharing host. Successful exploitation could execute code on the host system, potentially affecting the confidentiality, integrity, and availability of the system. The attack requires no privileges, but user interaction is required to initiate or participate in the sharing session.

CVSS SCORE: 8.8.

SEVERITY: Critical.

THREAT: The vulnerability is remotely reachable over a network, has low attack complexity, and requires no attacker privileges. A successful attack can result in remote code execution with high confidentiality, integrity, and availability impact. User interaction is required through participation in or initiation of a Remote Desktop sharing session.

EXPLOITS: This vulnerability is not publicly disclosed and is not reported as exploited. Exploit code maturity is classified as Unproven, and exploitation is assessed as Less Likely. The source does not confirm the existence of public exploit code, zero-day exploitation, or proof-of-concept exploit code.

TECHNICAL SUMMARY: The vulnerability is caused by a heap-based buffer overflow (CWE-122) in Windows Remote Desktop. An unauthorized attacker could participate in a Remote Desktop sharing session and send specially crafted clipboard data to the sharing host. Processing that malicious data can trigger the vulnerability and allow execution of code on the host. The attack vector is network-based, attack complexity is low, no privileges are required, and user interaction is required. Successful exploitation carries high potential impact to confidentiality, integrity, and availability.

EXPLOITABILITY: Affected systems include Windows 10 versions 1607, 1809, 21H2, and 22H2; Windows 11 versions 23H2, 24H2, 25H2, and 26H1; and Windows Server 2012, 2012 R2, 2016, 2019, 2022, and 2025, including listed Server Core installations. An attacker can attempt exploitation by sending specially crafted clipboard data while participating in a Remote Desktop sharing session.

BUSINESS IMPACT: Successful exploitation could allow unauthorized code execution on an affected host, creating significant risk to sensitive information, system integrity, and service availability. For organizations using vulnerable Remote Desktop environments, compromise of a host could disrupt business operations and expose data or systems accessible from that host.

WORKAROUND: No mitigations or workarounds are identified. An official fix is listed, making patch deployment the documented remediation path.

URGENCY: This vulnerability is rated Critical with a CVSS base score of 8.8. Its network attack vector, low attack complexity, lack of required attacker privileges, and potential for remote code execution make timely deployment important. Although exploitation is assessed as Less Likely and no exploitation is reported, affected Windows clients and servers should be prioritized for the official security update.