{"id":"CVE-2026-93689","aliases":["EUVD-2026-82985","GHSA-grx3-v6wv-8gq8"],"status":"published","title":"WinFsp through 2.2.26215 NULL Pointer Dereference via Fast I/O","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.","severity":{"version":"4.0","score":6.8,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00154,"percentile":0.04589,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-476"],"published":"2026-09-18T15:06:04Z","modified":"2026-10-28T11:19:49Z","products":[{"vendor":"winfsp","product":"winfsp"}],"references":[{"url":"https://github.com/winfsp/winfsp/commit/b8103265ec63fa87ac264c62bb796dbc38376652","tags":["patch","fix"]},{"url":"https://github.com/winfsp/winfsp","tags":["product","package"]},{"url":"https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L68-L73","tags":["technical-description","article"]},{"url":"https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L105-L114","tags":["technical-description","article"]},{"url":"https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L146-L152","tags":["technical-description","article"]},{"url":"https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/volume.c#L1059-L1060","tags":["technical-description","article"]},{"url":"https://github.com/winfsp/winfsp/releases/tag/v2.2B4","tags":["release-notes","advisory"]},{"url":"https://www.vulncheck.com/advisories/winfsp-through-2.2.26215-null-pointer-dereference-via-fast-i-o","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93689","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-grx3-v6wv-8gq8"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93689.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-93689","title":"WinFsp through 2.2.26215 NULL Pointer Dereference via Fast I/O","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.","status":"published","published":"2026-09-18T15:06:04.237Z","modified":"2026-09-24T14:23:05.325Z","cvss":[{"version":"4.0","score":6.8,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T14:19:54.122945Z"}],"euvd":[{"id":"EUVD-2026-82985","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.","status":"published","published":"2026-09-18T15:06:04Z","modified":"2026-09-24T14:23:05Z","cvss":[{"version":"4.0","score":6.8,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T17:27:57.035497Z"}],"ghsa":[{"id":"GHSA-grx3-v6wv-8gq8","title":"WinFsp through 2.2.26215 contains a null pointer dereference vulnerability in the kernel driver's...","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.","status":"published","published":"2026-09-18T18:31:41Z","modified":"2026-09-18T18:31:56Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"},{"version":"4.0","score":6.8,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T15:12:11.358904Z"}],"nvd":[{"id":"CVE-2026-93689","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.","status":"published","published":"2026-09-18T16:17:15.837Z","modified":"2026-09-22T20:25:55.87Z","cvss":[{"version":"4.0","score":6.8,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T14:12:49.70655Z"}],"osv":[{"id":"CVE-2026-93689","title":"WinFsp through 2.2.26215 NULL Pointer Dereference via Fast I/O","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.","status":"published","published":"2026-09-18T15:06:04.237Z","modified":"2026-10-28T11:19:49.930842538Z","cvss":[{"version":"4.0","score":6.8,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T15:45:20.931171Z"}]}}