diff --git a/src/dbus/qdbusutil.cpp b/src/dbus/qdbusutil.cpp
index 78338aa0545..84ce5ed78dc 100644
--- a/src/dbus/qdbusutil.cpp
+++ b/src/dbus/qdbusutil.cpp
@@ -407,6 +407,8 @@ namespace QDBusUtil
             return isValidUniqueConnectionName(busName);
 
         const auto parts = QStringView{busName}.split(u'.');
+        if (parts.size() < 2)
+            return false;
         for (QStringView part : parts) {
             if (part.isEmpty())
                 return false;
diff --git a/tests/auto/dbus/qdbusmarshall/tst_qdbusmarshall.cpp b/tests/auto/dbus/qdbusmarshall/tst_qdbusmarshall.cpp
index 355a65bc594..82dc9059e02 100644
--- a/tests/auto/dbus/qdbusmarshall/tst_qdbusmarshall.cpp
+++ b/tests/auto/dbus/qdbusmarshall/tst_qdbusmarshall.cpp
@@ -938,6 +938,10 @@ void tst_QDBusMarshall::sendCallErrors_data()
             << "org.freedesktop.DBus.Error.UnknownMethod"
             << "Method \"ping\" with signature \"\" on interface \"org.qtproject.autotests.qpong\" doesn't exist\n" << (const char*)0;
 
+    QTest::newRow("invalid-service-single-label") << "service" << objectPath << interfaceName << "ping" << QVariantList()
+            << "org.qtproject.QtDBus.Error.InvalidService"
+            << "Invalid service name: service" << "";
+
     QTest::newRow("invalid-service") << "this isn't valid" << objectPath << interfaceName << "ping" << QVariantList()
             << "org.qtproject.QtDBus.Error.InvalidService"
             << "Invalid service name: this isn't valid" << "";