diff --git a/smack-core/src/main/java/org/jivesoftware/smack/ConnectionConfiguration.java b/smack-core/src/main/java/org/jivesoftware/smack/ConnectionConfiguration.java
index e0b24a08f..89b6ec278 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/ConnectionConfiguration.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/ConnectionConfiguration.java
@@ -600,7 +600,7 @@ public abstract class ConnectionConfiguration {
      * @param <C> the resulting connection configuration type parameter.
      */
     public abstract static class Builder<B extends Builder<B, C>, C extends ConnectionConfiguration> {
-        private SecurityMode securityMode = SecurityMode.ifpossible;
+        private SecurityMode securityMode = SecurityMode.required;
         private DnssecMode dnssecMode = DnssecMode.disabled;
         private String keystorePath = System.getProperty("javax.net.ssl.keyStore");
         private String keystoreType = KeyStore.getDefaultType();
diff --git a/smack-core/src/testFixtures/java/org/jivesoftware/smack/DummyConnection.java b/smack-core/src/testFixtures/java/org/jivesoftware/smack/DummyConnection.java
index b49ab8d3e..d0864842b 100644
--- a/smack-core/src/testFixtures/java/org/jivesoftware/smack/DummyConnection.java
+++ b/smack-core/src/testFixtures/java/org/jivesoftware/smack/DummyConnection.java
@@ -225,6 +225,7 @@ public class DummyConnection extends AbstractXMPPConnection {
                         ConnectionConfiguration.Builder<Builder, DummyConnectionConfiguration> {
 
             private Builder() {
+                setSecurityMode(SecurityMode.disabled);
             }
 
             @Override