MSRC-CVE-2026-70161 — .NET 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 the privileges of the user account or service account running the affected process.

Security updates
11.0.100-rc.2 — https://github.com/dotnet/announcements/issues/453
9.0.319, 9.0.122 — https://support.microsoft.com/help/5130035
10.0.402 — https://support.microsoft.com/help/5130036
18.10.4 — https://learn.microsoft.com/en-us/visualstudio/releases/2026/release-notes
17.14.42 — https://learn.microsoft.com/en-us/visualstudio/releases/2022/release-notes

Vulnerabilities 1

High 7.3

CVE-2026-70161

.NET Elevation of Privilege Vulnerability

Improper limitation of a pathname to a restricted directory ('path traversal') in .NET allows an authorized attacker to elevate privileges locally.

Microsoft Microsoft Visual Studio 2022 version 17.14 .NET 9.0 runtime .NET 10.0 runtime Ubuntu Alpine

Oct 13, 2026

Revision history

2026-10-27 #3
Updated an acknowledgement. This is an informational change only.
2026-10-15 #2
Updated the Security Updates table to add KB article links for .NET 11.0 and download and KB article links for Microsoft Visual Studio. This is an informational change only; the fixed builds are unchanged.
2026-10-13 #1
Information published.

References

CVE-2026-70161 .NET Elevation of Privilege Vulnerability - HTML
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70161
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