diff --git a/connector/testfiles/testconfig/config.xml b/connector/testfiles/testconfig/config.xml
index 9a8aca7..dcf295f 100644
--- a/connector/testfiles/testconfig/config.xml
+++ b/connector/testfiles/testconfig/config.xml
@@ -55,7 +55,7 @@
         <maxRecvKbps>0</maxRecvKbps>
     </device>
     <gui enabled="true" tls="false" debugging="false">
-        <address>localhost:4001</address>
+        <address>127.0.0.1:4001</address>
         <user>nobody</user>
         <password>$2a$12$35MnbsQgQNn1hzPYK/lWXOaP.U5D2TO0nuuQy2M4gsqJB4ff4q2RK</password>
         <apikey>syncthingconnectortest</apikey>
@@ -63,7 +63,7 @@
     </gui>
     <ldap></ldap>
     <options>
-        <listenAddress>tcp://localhost:32452</listenAddress>
+        <listenAddress>tcp://127.0.0.1:32452</listenAddress>
         <globalAnnounceServer>default</globalAnnounceServer>
         <globalAnnounceEnabled>true</globalAnnounceEnabled>
         <localAnnounceEnabled>true</localAnnounceEnabled>
diff --git a/connector/tests/connectiontests.cpp b/connector/tests/connectiontests.cpp
index 7020aea..2baf208 100644
--- a/connector/tests/connectiontests.cpp
+++ b/connector/tests/connectiontests.cpp
@@ -118,7 +118,7 @@ void ConnectionTests::setUp()
     SyncthingTestInstance::start();
 
     cerr << "\n - Preparing connection ..." << endl;
-    m_connection.setSyncthingUrl(QStringLiteral("http://localhost:") + syncthingPort());
+    m_connection.setSyncthingUrl(QStringLiteral("http://127.0.0.1:") + syncthingPort());
 
     // keep track of status changes
     QObject::connect(&m_connection, &SyncthingConnection::statusChanged,
diff --git a/testhelper/syncthingtestinstance.cpp b/testhelper/syncthingtestinstance.cpp
index 155ce47..585ef55 100644
--- a/testhelper/syncthingtestinstance.cpp
+++ b/testhelper/syncthingtestinstance.cpp
@@ -76,7 +76,7 @@ void SyncthingTestInstance::start()
     // start st
     // clang-format off
     const QStringList args{
-        QStringLiteral("-gui-address=http://localhost:") + m_syncthingPort,
+        QStringLiteral("-gui-address=http://127.0.0.1:") + m_syncthingPort,
         QStringLiteral("-gui-apikey=") + m_apiKey,
         QStringLiteral("-home=") + configFile.absolutePath(),
         QStringLiteral("-no-browser"),