The vulnerability is a double free in Microsoft OpenSSH for Windows, enabling an authorized local attacker to gain elevated privileges. The flaw allows the attacker to execute code with higher permissions, potentially compromising system integrity and confidentiality. This represents an elevation of privilege weakness characterized by the double free mechanic (CWE-415) and the resulting resource exhaustion (CWE-400).

Microsoft Windows 10 versions 1809, 21H2, and 22H2; Microsoft Windows 11 versions 23H2, 24H2, 25H2, 26H2, and 26H1; Microsoft Windows Server 2019, Server 2019 (Server Core), Windows Server 2022, Windows Server 2025, and Windows Server 2025 (Server Core).

With a CVSS score of 7.8, the vulnerability is considered high severity. No EPSS score is available, and the vulnerability is not listed in the CISA KEV catalog, indicating it may not yet be widely exploited. The exploit requires the attacker to have local authorized access to the system; the double free can be triggered by a crafted input to the OpenSSH service, allowing escalation of privileges. The risk is therefore primarily confined to machines where OpenSSH for Windows is installed, and local users with sufficient permissions.