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TI-2026-51182 Aliases CVE-2026-72971GHSA-mq4h-r45f-27gp

Windows Container Isolation FS Filter Driver (unionfs.sys) Tampering Vulnerability

Priority LOW 25CWE-59Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Tampering
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Microsoft. Impact type from Microsoft.

Summary

Improper link resolution before file access ('link following') in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to perform tampering locally.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00364 30th percentileScored 2026-11-07
Fix Fixed Microsoft: 1 update

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftWindows 11 version 26H110.0.28000.0 to before 10.0.28000.270410.0.28000.2704Patch availableCNA
  • Windows 11 version 26H1 VendorMicrosoft Affected 10.0.28000.0 to before 10.0.28000.2704 Fixed in 10.0.28000.2704 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:*before 10.0.28000.2704VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:*before 10.0.28000.2704VulnerableMicrosoft
  • cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:* Versions before 10.0.28000.2704 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:* Versions before 10.0.28000.2704 Vulnerable ·Microsoft

Remediation

Microsoft 1 update

  • KB5121000
    Security Update
    • Windows 11 Version 26H1 for ARM64-based Systems 10.0.28000.2704
    • Windows 11 version 26H1 for x64-based Systems 10.0.28000.2704

Vendor assessments

Microsoft

Microsoft's page for this CVE →

Impact
Tampering
Exploited
No
Publicly disclosed
Yes
Exploitability
Exploitation Unlikely

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-72971
  2. 2026-10-03 Alias added: GHSA-mq4h-r45f-27gp

References

Patch 1

  • TI-2026-26194 Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-73128 Windows Shell Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2026-56567 Windows Update Stack Elevation of Privilege Vulnerability KEVCVSS 3.1HIGH 7.8
  • TI-2026-48395 Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability KEVCVSS 3.1HIGH 7.0
  • TI-2026-24734 Windows Shell Spoofing Vulnerability KEVCVSS 3.1MEDIUM 4.3
  • TI-2026-36364 HTTP.sys Denial of Service Vulnerability CVSS 3.1HIGH 7.5
See all 2533 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences