CVE-2026-93689: WinFsp through 2.2.26215 NULL Pointer Dereference via Fast I/O
WinFsp through 2.2.26215 contains a null pointer dereference vulnerability in the kernel driver's Fast I/O device control handler that fails to validate the volume context before use. An unprivileged local user can trigger a denial of service by opening the WinFsp control device and issuing FSPIOCTLTRANSACT requests, causing a system crash.
Affected Software
Event History
Frequently Asked Questions
Who can exploit this issue?
An unprivileged local user can trigger the denial of service. Exploitation requires local access and does not require user interaction.
What access is needed to trigger the crash?
The attacker needs to be able to open the WinFsp control device and issue FSP_IOCTL_TRANSACT requests. The provided information does not indicate that remote exploitation is possible.
What is the impact of successful exploitation?
Successful exploitation can cause a system crash, resulting in a denial of service. No confidentiality or integrity impact is identified in the supplied severity vector.