Microsoft Windows up to Server 2025 LUA File Virtualization Filter Driver toctou

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.1$5k-$25k0.68

Summaryinfo

A vulnerability was found in Microsoft Windows and classified as critical. The impacted element is an unknown function of the component LUA File Virtualization Filter Driver. Such manipulation leads to toctou. This vulnerability is uniquely identified as CVE-2026-27929. Local access is required to approach this attack. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Microsoft Windows. It has been rated as critical. Affected by this issue is an unknown code of the component LUA File Virtualization Filter Driver. The manipulation with an unknown input leads to a toctou vulnerability. Using CWE to declare the problem leads to CWE-367. The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the product to perform invalid actions when the resource is in an unexpected state. Impacted is confidentiality, integrity, and availability.

The weakness was disclosed 04/14/2026 as confirmed security update guide (Website). The advisory is shared for download at msrc.microsoft.com. This vulnerability is handled as CVE-2026-27929. The exploitation is known to be difficult. The attack needs to be approached locally. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 04/14/2026).

Upgrading to version 6.2.9200.26026, 6.3.9600.23132, 10.0.14393.9060, 10.0.17763.8644, 10.0.19044.7184, 10.0.19045.7184, 10.0.20348.5020, 10.0.22631.6936, 10.0.25398.2274, 10.0.26100.32690, 10.0.26200.8246 or 10.0.28000.1836 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

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Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.0
VulDB Meta Temp Score: 6.1

VulDB Base Score: 7.0
VulDB Temp Score: 6.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.0
Vendor Vector (Microsoft): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Toctou
CWE: CWE-367 / CWE-362
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Unproven
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔒
0-Day Time: 🔒
Exposure Time: 🔒

Upgrade: Windows 6.2.9200.26026/6.3.9600.23132/10.0.14393.9060/10.0.17763.8644/10.0.19044.7184/10.0.19045.7184/10.0.20348.5020/10.0.22631.6936/10.0.25398.2274/10.0.26100.32690/10.0.26200.8246/10.0.28000.1836

Timelineinfo

04/14/2026 VulDB entry created
04/14/2026 +0 days Advisory disclosed
04/14/2026 +0 days Countermeasure disclosed
04/14/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2026-27929 (🔒)
GCVE (CVE): GCVE-0-2026-27929
GCVE (VulDB): GCVE-100-357452
scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 04/14/2026 19:57
Updated: 04/14/2026 20:00
Changes: 04/14/2026 19:57 (38), 04/14/2026 20:00 (32)
Complete: 🔍
Cache ID: 216::103

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