cve-2026-40398

CVE-2026-40398 is an Important-rated Windows Remote Desktop Services elevation-of-privilege vulnerability disclosed by Microsoft on May 12, 2026, with a CVSS base score of 7.8. At the time of release, there was no public disclosure or active exploitation reported. This vulnerability is not a remote-code-execution emergency like BlueKeep, but it represents a privilege escalation within the Remote Desktop trust boundary, which administrators often underestimate. Such bugs can become part of an intrusion chain, making them significant for Windows security and enterprise IT environments. Discussions on WindowsForum cover the technical details, risk assessment, and mitigation strategies for this CVE.