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… (CVE-2026-93689)
WinFsp versions through 2.2.26215 have a null pointer dereference vulnerability in the kernel driver's Fast I/O device control handler. This flaw occurs because the volume context is not validated before use. An unprivileged local user can exploit this to cause a denial of service by opening the WinFsp control device and issuing specific requests, resulting in a system crash.
AI Analysis
Technical Summary
CVE-2026-93689 describes a null pointer dereference vulnerability in WinFsp up to version 2.2.26215. The kernel driver's Fast I/O device control handler fails to validate the volume context before use, allowing an unprivileged local user to trigger a denial of service. Exploitation involves opening the WinFsp control device and issuing FSP_IOCTL_TRANSACT requests, which leads to a system crash due to the null pointer dereference.
Potential Impact
The vulnerability allows an unprivileged local user to cause a denial of service by crashing the system. There is no impact on confidentiality or integrity reported. The CVSS score is 5.5 (medium severity), reflecting the local attack vector and denial of service impact.
Mitigation Recommendations
No patch or official fix information is provided. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict local user access to the WinFsp control device to mitigate exploitation risk.
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… (CVE-2026-93689)
Description
WinFsp versions through 2.2.26215 have a null pointer dereference vulnerability in the kernel driver's Fast I/O device control handler. This flaw occurs because the volume context is not validated before use. An unprivileged local user can exploit this to cause a denial of service by opening the WinFsp control device and issuing specific requests, resulting in a system crash.
CVSS v3.1
Score 5.5medium
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-93689 describes a null pointer dereference vulnerability in WinFsp up to version 2.2.26215. The kernel driver's Fast I/O device control handler fails to validate the volume context before use, allowing an unprivileged local user to trigger a denial of service. Exploitation involves opening the WinFsp control device and issuing FSP_IOCTL_TRANSACT requests, which leads to a system crash due to the null pointer dereference.
Potential Impact
The vulnerability allows an unprivileged local user to cause a denial of service by crashing the system. There is no impact on confidentiality or integrity reported. The CVSS score is 5.5 (medium severity), reflecting the local attack vector and denial of service impact.
Mitigation Recommendations
No patch or official fix information is provided. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict local user access to the WinFsp control device to mitigate exploitation risk.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-grx3-v6wv-8gq8
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-93689"]
- Database Specific Severity
- MODERATE
- Cvss Version
- 3.1
Threat ID: 6aade50b55bf5e2cf5edacad
Added to database: 09/19/2026, 01:27:39 UTC
Last enriched: 09/19/2026, 01:39:28 UTC
Last updated: 09/19/2026, 02:01:09 UTC
Views: 3
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