CVE-2026-93689
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.
CVSS
- Versión: 4.0
- 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
- Puntuación base: 6.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.15%
- Percentil entre todas las CVEs puntuadas: 4
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1068Exploitation for Privilege Escalationprivilege escalation95 % - Impacto principal
T1499.004Application or System Exploitationimpact90 %
Vulnerabilidad local (AV:L, PR:L) en controlador kernel sin validación de contexto; usuario sin privilegios causa null pointer dereference → DoS de aplicación/sistema (VA:H).
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-476
Referencias
- https://github.com/winfsp/winfsp
- https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L105-L114
- https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L146-L152
- https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/devctl.c#L68-L73
- https://github.com/winfsp/winfsp/blob/v2.2B4/src/sys/volume.c#L1059-L1060
- https://github.com/winfsp/winfsp/commit/b8103265ec63fa87ac264c62bb796dbc38376652
- https://github.com/winfsp/winfsp/releases/tag/v2.2B4
- https://www.vulncheck.com/advisories/winfsp-through-2.2.26215-null-pointer-dereference-via-fast-i-o
JSON original (NVD)
Mostrar
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"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED"
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"affected": [
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"affectedData": [
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],
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"weaknesses": [
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"description": [
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"descriptions": [
{
"lang": "en",
"value": "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."
}
],
"lastModified": "2026-09-22T20:25:55.870",
"sourceIdentifier": "disclosure@vulncheck.com"
}