diff --git a/src/plugins/platforms/wayland/qwaylanddatadevice.cpp b/src/plugins/platforms/wayland/qwaylanddatadevice.cpp
index fde0f71a250..7cdcd108cd1 100644
--- a/src/plugins/platforms/wayland/qwaylanddatadevice.cpp
+++ b/src/plugins/platforms/wayland/qwaylanddatadevice.cpp
@@ -151,9 +151,13 @@ void QWaylandDataDevice::data_device_drop()
 
 void QWaylandDataDevice::data_device_enter(uint32_t serial, wl_surface *surface, wl_fixed_t x, wl_fixed_t y, wl_data_offer *id)
 {
-    m_enterSerial = serial;
-    m_dragWindow = QWaylandWindow::fromWlSurface(surface)->window();
+    auto *dragWaylandWindow = QWaylandWindow::fromWlSurface(surface);
+    if (!dragWaylandWindow)
+        return; // Ignore foreign surfaces
+
+    m_dragWindow = dragWaylandWindow->window();
     m_dragPoint = calculateDragPosition(x, y, m_dragWindow);
+    m_enterSerial = serial;
 
     QMimeData *dragData = nullptr;
     Qt::DropActions supportedActions;
diff --git a/src/plugins/platforms/wayland/qwaylandinputdevice.cpp b/src/plugins/platforms/wayland/qwaylandinputdevice.cpp
index daad6f15c26..8231dd9c30c 100644
--- a/src/plugins/platforms/wayland/qwaylandinputdevice.cpp
+++ b/src/plugins/platforms/wayland/qwaylandinputdevice.cpp
@@ -555,6 +555,9 @@ void QWaylandInputDevice::Pointer::pointer_enter(uint32_t serial, struct wl_surf
 
     QWaylandWindow *window = QWaylandWindow::fromWlSurface(surface);
 
+    if (!window)
+        return; // Ignore foreign surfaces
+
     if (mFocus) {
         qCWarning(lcQpaWayland) << "The compositor sent a wl_pointer.enter event before sending a"
                                 << "leave event first, this is not allowed by the wayland protocol"
@@ -596,10 +599,12 @@ void QWaylandInputDevice::Pointer::pointer_leave(uint32_t time, struct wl_surfac
     if (!surface)
         return;
 
-    if (!QWaylandWindow::mouseGrab()) {
-        QWaylandWindow *window = QWaylandWindow::fromWlSurface(surface);
+    auto *window = QWaylandWindow::fromWlSurface(surface);
+    if (!window)
+        return; // Ignore foreign surfaces
+
+    if (!QWaylandWindow::mouseGrab())
         setFrameEvent(new LeaveEvent(window, mSurfacePos, mGlobalPos));
-    }
 
     invalidateFocus();
     mButtons = Qt::NoButton;
@@ -1264,9 +1269,13 @@ void QWaylandInputDevice::Touch::touch_down(uint32_t serial,
     if (!surface)
         return;
 
+    auto *window = QWaylandWindow::fromWlSurface(surface);
+    if (!window)
+        return; // Ignore foreign surfaces
+
     mParent->mTime = time;
     mParent->mSerial = serial;
-    mFocus = QWaylandWindow::fromWlSurface(surface);
+    mFocus = window;
     mParent->mQDisplay->setLastInputDevice(mParent, serial, mFocus);
     mParent->handleTouchPoint(id, wl_fixed_to_double(x), wl_fixed_to_double(y), Qt::TouchPointPressed);
 }
diff --git a/src/plugins/platforms/wayland/qwaylandqtkey.cpp b/src/plugins/platforms/wayland/qwaylandqtkey.cpp
index a60185bd641..19261973853 100644
--- a/src/plugins/platforms/wayland/qwaylandqtkey.cpp
+++ b/src/plugins/platforms/wayland/qwaylandqtkey.cpp
@@ -70,7 +70,11 @@ void QWaylandQtKeyExtension::zqt_key_v1_key(struct wl_surface *surface,
     }
 
     QWaylandInputDevice *dev = inputDevices.first();
-    QWaylandWindow *win = surface ? QWaylandWindow::fromWlSurface(surface) : dev->keyboardFocus();
+
+    auto *win = surface ? QWaylandWindow::fromWlSurface(surface) : nullptr;
+
+    if (!win)
+        win = dev->keyboardFocus();
 
     if (!win || !win->window()) {
         qWarning("qt_key_extension: handle_qtkey: No keyboard focus");
diff --git a/src/plugins/platforms/wayland/qwaylandscreen.cpp b/src/plugins/platforms/wayland/qwaylandscreen.cpp
index b2e3ce819b9..ee6f949aa59 100644
--- a/src/plugins/platforms/wayland/qwaylandscreen.cpp
+++ b/src/plugins/platforms/wayland/qwaylandscreen.cpp
@@ -190,8 +190,9 @@ QWaylandScreen * QWaylandScreen::waylandScreenFromWindow(QWindow *window)
 
 QWaylandScreen *QWaylandScreen::fromWlOutput(::wl_output *output)
 {
-    auto wlOutput = static_cast<QtWayland::wl_output *>(wl_output_get_user_data(output));
-    return static_cast<QWaylandScreen *>(wlOutput);
+    if (auto *o = QtWayland::wl_output::fromObject(output))
+        return static_cast<QWaylandScreen *>(o);
+    return nullptr;
 }
 
 void QWaylandScreen::output_mode(uint32_t flags, int width, int height, int refresh)
diff --git a/src/plugins/platforms/wayland/qwaylandsurface.cpp b/src/plugins/platforms/wayland/qwaylandsurface.cpp
index 03a1c1f526b..c35f01b56c3 100644
--- a/src/plugins/platforms/wayland/qwaylandsurface.cpp
+++ b/src/plugins/platforms/wayland/qwaylandsurface.cpp
@@ -65,7 +65,9 @@ QWaylandScreen *QWaylandSurface::oldestEnteredScreen()
 
 QWaylandSurface *QWaylandSurface::fromWlSurface(::wl_surface *surface)
 {
-    return static_cast<QWaylandSurface *>(static_cast<QtWayland::wl_surface *>(wl_surface_get_user_data(surface)));
+    if (auto *s = QtWayland::wl_surface::fromObject(surface))
+        return static_cast<QWaylandSurface *>(s);
+    return nullptr;
 }
 
 void QWaylandSurface::handleScreenRemoved(QScreen *qScreen)
@@ -79,6 +81,9 @@ void QWaylandSurface::surface_enter(wl_output *output)
 {
     auto addedScreen = QWaylandScreen::fromWlOutput(output);
 
+    if (!addedScreen)
+        return;
+
     if (m_screens.contains(addedScreen)) {
         qCWarning(lcQpaWayland)
                 << "Ignoring unexpected wl_surface.enter received for output with id:"
@@ -95,6 +100,10 @@ void QWaylandSurface::surface_enter(wl_output *output)
 void QWaylandSurface::surface_leave(wl_output *output)
 {
     auto *removedScreen = QWaylandScreen::fromWlOutput(output);
+
+    if (!removedScreen)
+        return;
+
     bool wasRemoved = m_screens.removeOne(removedScreen);
     if (!wasRemoved) {
         qCWarning(lcQpaWayland)
diff --git a/src/tools/qtwaylandscanner/qtwaylandscanner.cpp b/src/tools/qtwaylandscanner/qtwaylandscanner.cpp
index 56045e88058..7f3dc5ad6bb 100644
--- a/src/tools/qtwaylandscanner/qtwaylandscanner.cpp
+++ b/src/tools/qtwaylandscanner/qtwaylandscanner.cpp
@@ -986,6 +986,7 @@ bool Scanner::process()
             printf("\n");
             printf("        struct ::%s *object() { return m_%s; }\n", interfaceName, interfaceName);
             printf("        const struct ::%s *object() const { return m_%s; }\n", interfaceName, interfaceName);
+            printf("        static %s *fromObject(struct ::%s *object);\n", interfaceName, interfaceName);
             printf("\n");
             printf("        bool isInitialized() const;\n");
             printf("\n");
@@ -1130,6 +1131,16 @@ bool Scanner::process()
             printf("    }\n");
             printf("\n");
 
+            printf("    %s *%s::fromObject(struct ::%s *object)\n", interfaceName, interfaceName, interfaceName);
+            printf("    {\n");
+            if (hasEvents) {
+                printf("        if (wl_proxy_get_listener((struct ::wl_proxy *)object) != (void *)&m_%s_listener)\n", interfaceName);
+                printf("            return nullptr;\n");
+            }
+            printf("        return static_cast<%s *>(%s_get_user_data(object));\n", interfaceName, interfaceName);
+            printf("    }\n");
+            printf("\n");
+
             printf("    bool %s::isInitialized() const\n", interfaceName);
             printf("    {\n");
             printf("        return m_%s != nullptr;\n", interfaceName);