diff --git a/Chapter4_WPF_Databinding/Exercise1.Tests/packages.config b/Chapter4_WPF_Databinding/Exercise1.Tests/packages.config
index 1e340dc..e7ee902 100644
--- a/Chapter4_WPF_Databinding/Exercise1.Tests/packages.config
+++ b/Chapter4_WPF_Databinding/Exercise1.Tests/packages.config
@@ -3,7 +3,7 @@
   <package id="Guts.Client" version="3.0.0" targetFramework="net472" />
   <package id="Guts.Client.Shared" version="3.0.0" targetFramework="net472" />
   <package id="Microsoft.AspNet.WebApi.Client" version="5.2.7" targetFramework="net461" />
-  <package id="Newtonsoft.Json" version="12.0.3" targetFramework="net472" />
+  <package id="Newtonsoft.Json" version="13.0.1" targetFramework="net472" />
   <package id="NUnit" version="3.12.0" targetFramework="net472" />
   <package id="NUnit3TestAdapter" version="3.17.0" targetFramework="net472" />
 </packages>
\ No newline at end of file