undici vulnerable to cookie attribute injection via unsanitized domain and unparsed setCookie fields
CVE-2026-16729
Summary
Authentication bypass by spoofing in ASP.NET Core allows an authorized attacker to elevate privileges over a network.
Products covered
Microsoft Visual Studio 2026 version 18.10
Microsoft Visual Studio 2022 version 17.14
Microsoft.AspNetCore.Authentication.Negotiate on .NET 10.0 installed on Windows
Microsoft.AspNetCore.Authentication.Negotiate on .NET 10.0 installed on Linux
Microsoft.AspNetCore.Authentication.Negotiate on .NET 10.0 installed on Mac OS
Microsoft.AspNetCore.Authentication.Negotiate on .NET 8.0 installed on Windows
Microsoft.AspNetCore.Authentication.Negotiate on .NET 8.0 installed on Linux
Microsoft.AspNetCore.Authentication.Negotiate on .NET 8.0 installed on Mac OS
Show 3 more products
Microsoft.AspNetCore.Authentication.Negotiate on .NET 9.0 installed on Windows
Microsoft.AspNetCore.Authentication.Negotiate on .NET 9.0 installed on Linux
Microsoft.AspNetCore.Authentication.Negotiate on .NET 9.0 installed on Mac OS
Remediation
Release Notes
Vendor-listed fixes
18.10.4
17.14.42
10.0.13
8.0.32
9.0.21
CVEs in this advisory 1
Update history
What changed in later vendor updates
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- The vendor changed the advisory's last-updated date.
Updates
- Published by Microsoft Security Response Center
The publication date reported by the vendor.
- Added to SecurityAlert
We collected the advisory from the official source.
- Updated by Microsoft Security Response Center
The vendor changed the advisory after it was first published.
- Confirmed at the source
Our collector saw this advisory during a later source check.