CVE-2026-50398 is a Windows Media Elevation of Privilege vulnerability caused by a race condition involving concurrent execution using a shared resource with improper synchronization. Microsoft rates it High severity with a CVSS v3.1 base score of 8.8 and temporal score of 7.7. The vector is NETWORK, LOW attack complexity, LOW privileges required, and NO user interaction, with HIGH impacts to confidentiality, integrity, and availability. Microsoft states exploitation is not publicly disclosed and not known to be exploited, with exploit code maturity UNPROVEN. The FAQ says successful exploitation could grant SYSTEM privileges. For enterprise environments, the network attack vector and no user interaction increase relevance, but Microsoft’s exploitation likelihood is not elevated.

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. Successful exploitation could lead to SYSTEM privileges.
- Exploitation likelihood: Exploitation Unlikely; vector is NETWORK with LOW attack complexity, LOW privileges required, and NO user interaction.
- Severity for enterprise: High technical severity. Network exposure and no user interaction increase relevance, but current disclosure and exploitation status indicate lower immediate risk than an actively exploited issue.
- Patch status: available; customer action required.

Affected systems:
- Windows 11 24H2
- Windows 11 25H2
- Windows 11 26H1
- Windows 11 unspecified
- Windows Server 2025