diff --git a/src/Imagination.LWM2M.Common/project.json b/src/Imagination.LWM2M.Common/project.json
old mode 100644
new mode 100755
index 0f72984..c697f0e
--- a/src/Imagination.LWM2M.Common/project.json
+++ b/src/Imagination.LWM2M.Common/project.json
@@ -16,7 +16,7 @@
 
   "dependencies": {
     "CoAP": "1.1.0",
-    "DTLS.Net": "1.0.18",
+    "DTLS.Net": "1.0.21",
     "Imagination.Common": "1.0.4-*",
     "Imagination.Service.Common": "1.0.0-*",
     "Imagination.Model": "1.0.3-*"
diff --git a/test/LWM2MTestClient/project.json b/test/LWM2MTestClient/project.json
old mode 100644
new mode 100755
index 9ee4446..05f70ac
--- a/test/LWM2MTestClient/project.json
+++ b/test/LWM2MTestClient/project.json
@@ -6,7 +6,7 @@
 
   "dependencies": {
     "CoAP": "1.1.0",
-    "DTLS.Net": "1.0.18",
+    "DTLS.Net": "1.0.21",
     "Imagination.LWM2M.Common": "1.0.5-*",
     "Microsoft.Extensions.Configuration.EnvironmentVariables": "1.0.0-rc2-final",
     "Microsoft.Extensions.Configuration.Json": "1.0.0-rc2-final",