CVE-2026-50360 is a Windows SMB Server elevation of privilege vulnerability caused by an incorrect implementation of an authentication algorithm. Microsoft rates it as High severity with a CVSS v3.1 base score of 8.8 and temporal score of 7.7. The vector is NETWORK, attack complexity is LOW, privileges required are LOW, and user interaction is NONE. If successfully exploited, an attacker could gain administrator privileges, with HIGH confidentiality, integrity, and availability impact. Microsoft reports no public disclosure and no known exploitation; exploit code maturity is UNPROVEN. Because it affects a network service and requires only low privileges, it is relevant for enterprise environments, especially systems exposing SMB services.

Highlights:
- CVSS scores: Base 8.8 - Temporal 7.7
- Exploit status & code maturity: Publicly Disclosed: No; Exploited: No; Exploit Code Maturity: UNPROVEN.
- Impact: Elevation of Privilege; confidentiality HIGH, integrity HIGH, availability HIGH.
- Exploitation likelihood: Exploitation Unlikely; network vector with LOW attack complexity, LOW privileges required, and NO user interaction.
- Severity for enterprise: High. Network-reachable SMB servers increase exposure, but the attack requires low existing privileges and there is no reported exploitation.
- Patch status: available; customer action required.

Affected systems:
- Windows 10 21H2
- Windows 10 22H2
- Windows 11 24H2
- Windows 11 25H2
- Windows 11 26H1
- Windows 11 unspecified
- Windows Server 2022
- Windows Server 2025