ZDI-26-617: Microsoft Windows MIDI Service Incorrect Permission Assignment Local Privilege Escalation Vulnerability
Published Sep 8, 2026
·Updated
This vulnerability allows local attackers to escalate privileges on affected installations of Microsoft Windows. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The ZDI has assigned a CVSS rating of 7.8. The following CVEs are assigned: CVE-2026-66804.
Affected Software
1 affected component
Microsoft Windows
Event History
Sep 8, 2026
Advisory Published
via ZDI·05:00 AM
Data Sourced
via ZDI·05:00 AM
Description
Frequently Asked Questions
1
What level of access does an attacker need before exploiting this issue?
The attacker must already be able to execute low-privileged code locally on the affected Windows system. The issue is therefore relevant after an initial foothold, such as execution under a standard user context.
2
What is the likely security impact after successful exploitation?
Successful exploitation allows a local attacker to escalate privileges on the affected installation. The advisory assigns a CVSS rating of 7.8.