Windows Fast FAT File System Driver Information Disclosure Vulnerability
CVE-2026-70277
Summary
Use of uninitialized resource in Windows Failover Cluster allows an unauthorized attacker to disclose information over a network.
Products covered
Windows 10 Version 1809 for 32-bit Systems
Windows 10 Version 1809 for x64-based Systems
Windows Server 2019
Windows Server 2019 (Server Core installation)
Windows Server 2022
Windows Server 2022 (Server Core installation)
Windows Server 2025 (Server Core installation)
Windows Server 2025
Remediation
Install KB5122876. Install KB5122882. Install KB5122871.
Vendor-listed fixes
10.0.17763.9245
10.0.20348.5622
10.0.26100.33438
CVEs in this advisory 1
Updates
- Published by Microsoft Security Response Center
The publication date reported by the vendor.
- Added to SecurityAlert
We collected the advisory from the official source.
- Confirmed at the source
Our collector saw this advisory during a later source check.