{"id":"CVE-2026-93689","published":"2026-09-18T16:17:15.837","lastModified":"2026-09-22T20:25:55.870","description":"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 FSP_IOCTL_TRANSACT requests, causing a system crash.","cvssScore":5.5,"cvssSeverity":"MEDIUM","cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cwes":["CWE-476"],"vendors":[],"products":[],"references":[{"url":"https://github.com/winfsp/winfsp","tags":[]},{"url":"https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L105-L114","tags":[]},{"url":"https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L146-L152","tags":[]},{"url":"https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L68-L73","tags":[]},{"url":"https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/volume.c#L1059-L1060","tags":[]},{"url":"https://github.com/winfsp/winfsp/commit/b8103265ec63fa87ac264c62bb796dbc38376652","tags":[]},{"url":"https://github.com/winfsp/winfsp/releases/tag/v2.2B4","tags":[]},{"url":"https://www.vulncheck.com/advisories/winfsp-through-2.2.26215-null-pointer-dereference-via-fast-i-o","tags":[]}],"exploitRefs":[{"url":"https://github.com/winfsp/winfsp","tags":[]},{"url":"https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L105-L114","tags":[]},{"url":"https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L146-L152","tags":[]},{"url":"https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L68-L73","tags":[]},{"url":"https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/volume.c#L1059-L1060","tags":[]},{"url":"https://github.com/winfsp/winfsp/commit/b8103265ec63fa87ac264c62bb796dbc38376652","tags":[]},{"url":"https://github.com/winfsp/winfsp/releases/tag/v2.2B4","tags":[]}],"hasPoc":true,"ai":null}