diff --git a/src/test/denialofservice_tests.cpp b/src/test/denialofservice_tests.cpp
--- a/src/test/denialofservice_tests.cpp
+++ b/src/test/denialofservice_tests.cpp
@@ -285,7 +285,10 @@
         LOCK(cs_main);
         Misbehaving(dummyNode1.GetId(), 10, "");
     }
-    peerLogic->SendMessages(config, &dummyNode1, interruptDummy);
+    {
+        LOCK2(cs_main, dummyNode1.cs_sendProcessing);
+        peerLogic->SendMessages(config, &dummyNode1, interruptDummy);
+    }
     BOOST_CHECK(!connman->IsBanned(addr1));
     {
         LOCK(cs_main);