Executive brief
Windows Fast FAT Driver is a core Windows component responsible for reading and writing data to storage devices using the FAT file system. A stack-based buffer overflow vulnerability allows an authenticated user with local access to execute arbitrary code and escalate their privileges on the system, potentially compromising the entire Windows installation.
Technical details
A stack-based buffer overflow exists in the Windows Fast FAT Driver when processing specially crafted FAT file system metadata. The vulnerability requires local authentication and file system access to exploit. An attacker with these preconditions can trigger the overflow by creating a malicious FAT volume or triggering the driver to parse malicious filesystem structures, leading to stack corruption and arbitrary code execution with kernel privileges. Microsoft has released patches to address this issue.
Affected products
- Microsoft Windows Fast FAT Driver <UNKNOWN>
Timeline
- 2026-09-08: disclosed