diff --git a/streams/src/main/java/org/apache/kafka/streams/processor/internals/DefaultStateUpdater.java b/streams/src/main/java/org/apache/kafka/streams/processor/internals/DefaultStateUpdater.java
index addef5a9f1565..bb2f2ddd5b755 100644
--- a/streams/src/main/java/org/apache/kafka/streams/processor/internals/DefaultStateUpdater.java
+++ b/streams/src/main/java/org/apache/kafka/streams/processor/internals/DefaultStateUpdater.java
@@ -320,7 +320,7 @@ private KafkaFutureImpl<Uuid> restoreConsumerInstanceId(final Duration timeout)
 
 
         private void handleRuntimeException(final RuntimeException runtimeException) {
-            log.error("An unexpected error occurred within the state updater thread: " + runtimeException);
+            log.error("An unexpected error occurred within the state updater thread: {}", String.valueOf(runtimeException));
             addToExceptionsAndFailedTasksThenClearUpdatingAndPausedTasks(runtimeException);
             isRunning.set(false);
         }
diff --git a/streams/src/test/java/org/apache/kafka/streams/processor/internals/DefaultStateUpdaterTest.java b/streams/src/test/java/org/apache/kafka/streams/processor/internals/DefaultStateUpdaterTest.java
index 25f3f0e587f75..adc71ebc116e1 100644
--- a/streams/src/test/java/org/apache/kafka/streams/processor/internals/DefaultStateUpdaterTest.java
+++ b/streams/src/test/java/org/apache/kafka/streams/processor/internals/DefaultStateUpdaterTest.java
@@ -290,7 +290,11 @@ private void shouldThrowIfAddingTasksWithSameId(final Task task1, final Task tas
         stateUpdater.add(task2);
 
         verifyFailedTasks(IllegalStateException.class, task1);
-        assertFalse(stateUpdater.isRunning());
+        waitForCondition(
+            () -> !stateUpdater.isRunning(),
+            VERIFICATION_TIMEOUT,
+            "Did not switch to non-running within the given timeout!"
+        );
     }
 
     @Test
@@ -1015,6 +1019,8 @@ public void shouldPauseActiveTaskAndTransitToUpdateStandby() throws Exception {
         verifyRestoredActiveTasks();
         verifyUpdatingTasks(task2);
         verifyExceptionsAndFailedTasks();
+        // shutdown ensures that the test does not end before changelog reader methods verified below are called
+        stateUpdater.shutdown(Duration.ofMinutes(1));
         verify(changelogReader, times(1)).enforceRestoreActive();
         verify(changelogReader, times(1)).transitToUpdateStandby();
     }
@@ -1152,6 +1158,8 @@ public void shouldIdleWhenAllTasksPaused() throws Exception {
     public void shouldResumeStandbyTask() throws Exception {
         final StandbyTask task = standbyTask(TASK_0_0, Set.of(TOPIC_PARTITION_A_0)).inState(State.RUNNING).build();
         shouldResumeStatefulTask(task);
+        // shutdown ensures that the test does not end before changelog reader methods verified below are called
+        stateUpdater.shutdown(Duration.ofMinutes(1));
         verify(changelogReader, times(2)).transitToUpdateStandby();
     }