diff --git a/src/core/model/random-variable-stream.cc b/src/core/model/random-variable-stream.cc
index dca094d0c..ce1ff8417 100644
--- a/src/core/model/random-variable-stream.cc
+++ b/src/core/model/random-variable-stream.cc
@@ -1655,6 +1655,10 @@ void EmpiricalRandomVariable::Validate ()
         }
       prior = current;
     }
+  if (prior.cdf != 1.0)
+    {
+      NS_FATAL_ERROR ("CDF does not cover the whole distribution");
+    }
   m_validated = true;
 }