System.Net.Tests.HttpListenerAuthenticationTests fail with UnexpectedFailure

[jkotas]

Running assembly:System.Net.HttpListener.Tests, Version=11.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51
[FAIL] System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails
Assert.Equal() Failure: Values differ
Expected: Unauthorized
Actual:   UnexpectedFailure
   at System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails() in /_/src/libraries/System.Net.HttpListener/tests/HttpListenerAuthenticationTests.cs:line 273

Build Information

Build: https://dev.azure.com/dnceng-public/cbb18261-c48f-4abb-8651-8cdcb5474649/_build/results?buildId=1622350
Build error leg or test failing: System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails
Pull request: https://github.com/dotnet/runtime.git/pull/135172

Error Message

DO NOT USE JSON BELOW IF THIS IS A BUILD BREAK otherwise build analysis will allow pull requests to merge that break the build worse. For a build break, do not use this issue form. Make a regular new issue.

Fill the error message using step by step known issues guidance.

{
  "ErrorMessage": ["HttpListenerAuthenticationTests","UnexpectedFailure"],
  "ErrorPattern": "",
  "BuildRetry": false,
  "ExcludeConsoleLog": false
}

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1622350
Error message validated: [HttpListenerAuthenticationTests UnexpectedFailure]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 10/4/2026 6:14:52 PM UTC

Report

Build	Repository	Test	Pull Request
1626128	dotnet/runtime	System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails
1625894	dotnet/runtime	System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails
1625566	dotnet/runtime	System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails
1624629	dotnet/runtime	System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails
1624450	dotnet/runtime	System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails
1624339	dotnet/runtime	System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails	#135088
1624014	dotnet/runtime	System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails
1623223	dotnet/runtime	System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails
1622921	dotnet/runtime	System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails	#135177
1622855	dotnet/runtime	System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails	#135174
1622785	dotnet/runtime	System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails
1622350	dotnet/runtime	System.Net.Tests.HttpListenerAuthenticationTests.ExtendedProtectionSelectorDelegate_IncreasesPolicyBetweenNtlmLegs_AuthenticationFails	#135172

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
0	12	12

[dotnet-policy-service]

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