MSRC-CVE-2026-42828 — Windows Projected File System Elevation of Privilege Vulnerability

Summary

Impact: Elevation of Privilege. Microsoft rating: Important. Not known to be exploited — Exploitation Less Likely. Customer action: Required.

Details

What privileges could be gained by an attacker who successfully exploited this vulnerability?
An attacker who successfully exploited this vulnerability could gain SYSTEM privileges.

Security updates
10.0.20348.5256 — https://support.microsoft.com/help/5094128
10.0.17763.8880 — https://support.microsoft.com/help/5094123
10.0.19044.7417 — https://support.microsoft.com/help/5094127
10.0.26100.32995 — https://support.microsoft.com/help/5094125
10.0.26200.8655 — https://support.microsoft.com/help/5094126
10.0.22631.7219 — https://support.microsoft.com/help/5093998
10.0.28000.2269 — https://support.microsoft.com/help/5095051

Vulnerabilities 1

High 7.8

CVE-2026-42828

Windows Projected File System Elevation of Privilege Vulnerability

Buffer over-read in Windows Projected File System Filter Driver allows an authorized attacker to elevate privileges locally.

Microsoft Windows Server 2019 Windows Server 2019 (Server Core installation) Windows 10 Version 1809 Windows

Jun 9, 2026

Revision history

2026-06-17 #2
Acknowledgement added. This is an informational change only.
2026-06-09 #1
Information published.

References

CVE-2026-42828 Windows Projected File System Elevation of Privilege Vulnerability - HTML
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42828
Microsoft Exploitability Index
https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1
Microsoft Support Lifecycle
https://support.microsoft.com/lifecycle
Common Vulnerability Scoring System
https://www.first.org/cvss