CVE-2026-85909: Windows Universal Disk Format File System Driver (UDFS) Information Disclosure Vulnerability
Out-of-bounds read in Windows Universal Disk Format File System Driver (UDFS) allows an authorized attacker to disclose information locally.
Other sources
Windows Universal Disk Format File System Driver (UDFS) Information Disclosure Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
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Fixed in 10.0.14393.9612Patch KB5126868 - Upgrade
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Fixed in 6.3.9600.23470Patch KB5126836 - Upgrade
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Fixed in 10.0.26300.9711Patch KB5127648 - Upgrade
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Fixed in 6.2.9200.26434Patch KB5126835 - Upgrade
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Fixed in 10.0.19044.7807Patch KB5126657 - Upgrade
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Fixed in 10.0.28000.3231Patch KB5127646 - Upgrade
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Fixed in 10.0.26100.9711Patch KB5127648 - Upgrade
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Fixed in 10.0.22631.7652Patch KB5126653 - Upgrade
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Fixed in 10.0.26100.33650Patch KB5126646 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26200.9711Patch KB5127648 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.20348.5761Patch KB5126655 - Upgrade
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Fixed in 10.0.17763.9376Patch KB5126651
Event History
Frequently Asked Questions
Who can exploit this vulnerability?
An attacker must already be authorized on the affected system and be able to act locally. The provided vector indicates low attack complexity, no user interaction requirement, and no requirement for elevated privileges beyond low privileges.
What is the expected impact if exploitation succeeds?
Successful exploitation can disclose information from the affected system. The supplied impact metrics indicate high confidentiality impact, with no integrity or availability impact.
Which systems are identified as affected?
The affected software list includes Microsoft Windows 10, Windows 11, Windows Server 2012, Windows Server 2012 R2, Windows Server 2016, Windows Server 2019, Windows Server 2022, and Windows Server 2025.