Executive brief
A security vulnerability exists in a core Windows component responsible for managing storage spaces and disk virtualization. An attacker who already has basic access to a computer could exploit this flaw to gain full administrative control over the system. This could allow them to view sensitive data, install malicious software, or disrupt business operations.
Technical details
A privilege escalation vulnerability exists in the Windows Storage Spaces driver (Spaceport.sys) due to missing authentication for a critical function (CWE-306). The vulnerability is exploitable locally by an authenticated user with low privileges. By interacting with the vulnerable driver function, an attacker can bypass security checks to execute code or perform actions with elevated system-level permissions. Microsoft has released security updates to address this issue across multiple versions of Windows 10, Windows 11, and Windows Server.
Affected products
- Microsoft Windows 10 1607, 1809, 21H2, 22H2
- Microsoft Windows 11 24H2, 25H2, 26H1
- Microsoft Windows Server 2016 Standard and Server Core
Timeline
- 2026-07-14: disclosed: Initial publication by Microsoft and NVD
- 2026-07-14: advisory: Microsoft Security Update Guide published