CVSS 3.1
5.5 mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:NCVE-2026-113771 Windows Container Isolation FS Filter Driver (unionfs.sys) Elevation of Privilege Vulnerability
Medium (5.5) in microsoft windows 11 version 26h1. EPSS 0.4% estimated probability of exploitation activity in the next 30 days.
Off-by-one error in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to elevate privileges locally.
Severity
- EPSS
- 0.4% estimated probability of exploitation activity in the next 30 days; 34th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: total, assessed 2026-11-10. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-193 Off-by-one Error
- Published
- Modified
- Assigned by
- microsoft (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
- microsoft:windows 11 version 26h1
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| Microsoft Windows 11 version 26H1 | from 10.0.28000.0 before 10.0.28000.3501 |