diff --git a/src/core/devices/nm-device-ethernet.c b/src/core/devices/nm-device-ethernet.c
index c96cd158f0..638c9b6937 100644
--- a/src/core/devices/nm-device-ethernet.c
+++ b/src/core/devices/nm-device-ethernet.c
@@ -1747,7 +1747,7 @@ new_default_connection(NMDevice *self)
     if (dev)
         uprop = udev_device_get_property_value(dev, "NM_AUTO_DEFAULT_LINK_LOCAL_ONLY");
 
-    if (nm_udev_utils_property_as_boolean(uprop)) {
+    if (_nm_utils_ascii_str_to_bool(uprop, FALSE)) {
         setting = nm_setting_ip4_config_new();
         g_object_set(setting,
                      NM_SETTING_IP_CONFIG_METHOD,
diff --git a/src/libnm-platform/nm-platform.c b/src/libnm-platform/nm-platform.c
index 9a610e4a3c..54b251f384 100644
--- a/src/libnm-platform/nm-platform.c
+++ b/src/libnm-platform/nm-platform.c
@@ -1477,7 +1477,7 @@ nm_platform_link_get_unmanaged(NMPlatform *self, int ifindex, gboolean *unmanage
     const char *value;
 
     if (nm_platform_link_get_udev_property(self, ifindex, "NM_UNMANAGED", &value)) {
-        NM_SET_OUT(unmanaged, nm_udev_utils_property_as_boolean(value));
+        NM_SET_OUT(unmanaged, _nm_utils_ascii_str_to_bool(value, FALSE));
         return TRUE;
     }