diff --git a/src/DemaConsulting.SarifMark/DemaConsulting.SarifMark.csproj b/src/DemaConsulting.SarifMark/DemaConsulting.SarifMark.csproj
index 5c70bc9..867441c 100644
--- a/src/DemaConsulting.SarifMark/DemaConsulting.SarifMark.csproj
+++ b/src/DemaConsulting.SarifMark/DemaConsulting.SarifMark.csproj
@@ -61,7 +61,7 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="Polyfill" Version="9.12.0">
+    <PackageReference Include="Polyfill" Version="9.13.0">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>