diff --git a/src/libraries/tests.proj b/src/libraries/tests.proj
index f9f9f94a8204e..161e8e9603218 100644
--- a/src/libraries/tests.proj
+++ b/src/libraries/tests.proj
@@ -68,6 +68,8 @@
 
   <!-- wasm EAT/AOT -->
   <ItemGroup Condition="'$(TargetOS)' == 'Browser' and '$(RunDisabledWasmTests)' != 'true' and '$(EnableAggressiveTrimming)' == 'true'">
+    <!-- https://github.com/dotnet/runtime/issues/86916 -->
+    <ProjectExclusions Include="$(MSBuildThisFileDirectory)System.Formats.Cbor\tests\System.Formats.Cbor.Tests.csproj" />
   </ItemGroup>
 
   <!-- Wasm aot on all platforms -->