diff -up usbguard-1.0.0/configure.ac.orig usbguard-1.0.0/configure.ac
--- usbguard-1.0.0/configure.ac.orig	2022-08-16 10:24:34.345570913 +0200
+++ usbguard-1.0.0/configure.ac	2022-08-16 10:24:34.307571236 +0200
@@ -399,7 +399,7 @@ if test "x$with_dbus" = xyes; then
   #
   # Check for required D-Bus modules
   #
-  PKG_CHECK_MODULES([dbus], [dbus-1 gio-2.0],
+  PKG_CHECK_MODULES([dbus], [dbus-1 gio-2.0 polkit-gobject-1],
   [AC_DEFINE([HAVE_DBUS], [1], [Required GDBus API available])
   dbus_summary="system-wide; $dbus_CFLAGS $dbus_LIBS"],
   [AC_MSG_FAILURE([Required D-Bus modules (dbus-1, gio-2.0) not found!])]
diff -up usbguard-1.0.0/src/DBus/DBusBridge.cpp.orig usbguard-1.0.0/src/DBus/DBusBridge.cpp
--- usbguard-1.0.0/src/DBus/DBusBridge.cpp.orig	2022-08-16 10:24:34.312571194 +0200
+++ usbguard-1.0.0/src/DBus/DBusBridge.cpp	2022-08-16 10:28:28.595587136 +0200
@@ -21,6 +21,8 @@
 #endif
 
 #include "DBusBridge.hpp"
+#include <polkit/polkit.h>
+
 namespace usbguard
 {
   DBusBridge::DBusBridge(GDBusConnection* const gdbus_connection,
@@ -74,9 +76,19 @@ namespace usbguard
     return;
   }
 
+  #define DBUS_AUTH_CHECK \
+      GDBusError authErrorCode = G_DBUS_ERROR_FAILED; \
+      const gchar* authErrorMessage = NULL; \
+      if (! isAuthorizedByPolkit(invocation, &authErrorCode, &authErrorMessage)) { \
+        g_dbus_method_invocation_return_error_literal(invocation, G_DBUS_ERROR, authErrorCode, authErrorMessage); \
+        return; \
+      }
+
   void DBusBridge::handleRootMethodCall(const std::string& method_name, GVariant* parameters, GDBusMethodInvocation* invocation)
   {
     if (method_name == "getParameter") {
+      DBUS_AUTH_CHECK
+
       const char* name_cstr = nullptr;
       g_variant_get(parameters, "(&s)", &name_cstr);
       std::string name(name_cstr);
@@ -86,6 +98,8 @@ namespace usbguard
     }
 
     if (method_name == "setParameter") {
+      DBUS_AUTH_CHECK
+
       const char* name_cstr = nullptr;
       const char* value_cstr = nullptr;
       g_variant_get(parameters, "(&s&s)", &name_cstr, &value_cstr);
@@ -104,6 +118,8 @@ namespace usbguard
   void DBusBridge::handlePolicyMethodCall(const std::string& method_name, GVariant* parameters, GDBusMethodInvocation* invocation)
   {
     if (method_name == "listRules") {
+      DBUS_AUTH_CHECK
+
       const char* label_cstr = nullptr;
       g_variant_get(parameters, "(&s)", &label_cstr);
       std::string label(label_cstr);
@@ -136,6 +152,8 @@ namespace usbguard
     }
 
     if (method_name == "appendRule") {
+      DBUS_AUTH_CHECK
+
       const char* rule_spec_cstr = nullptr;
       uint32_t parent_id = 0;
       gboolean temporary = false;
@@ -147,6 +165,8 @@ namespace usbguard
     }
 
     if (method_name == "removeRule") {
+      DBUS_AUTH_CHECK
+
       uint32_t rule_id = 0;
       g_variant_get(parameters, "(u)", &rule_id);
       removeRule(rule_id);
@@ -163,6 +183,8 @@ namespace usbguard
     GDBusMethodInvocation* invocation)
   {
     if (method_name == "listDevices") {
+      DBUS_AUTH_CHECK
+
       const char* query_cstr = nullptr;
       g_variant_get(parameters, "(&s)", &query_cstr);
       std::string query(query_cstr);
@@ -195,6 +217,8 @@ namespace usbguard
     }
 
     if (method_name == "applyDevicePolicy") {
+      DBUS_AUTH_CHECK
+
       uint32_t device_id = 0;
       uint32_t target_integer = 0;
       gboolean permanent = false;
@@ -344,6 +368,135 @@ namespace usbguard
 
     return builder;
   }
+
+  std::string DBusBridge::formatGError(GError* error)
+  {
+    if (error) {
+      std::stringstream formatGError;
+      formatGError << error->message << " (code " << error->code << ")";
+      return formatGError.str();
+    }
+    else {
+      return "unknown error";
+    }
+  }
+
+  bool DBusBridge::isAuthorizedByPolkit(GDBusMethodInvocation* invocation, GDBusError* authErrorCode,
+    const gchar** authErrorMessage)
+  {
+    GError* error = NULL;
+    USBGUARD_LOG(Trace) << "Extracting bus name...";
+    const gchar* const /*no-free!*/ bus_name = g_dbus_method_invocation_get_sender (invocation);
+
+    if (! bus_name) {
+      USBGUARD_LOG(Trace) << "Failed to extract bus name.";
+      *authErrorCode = G_DBUS_ERROR_AUTH_FAILED;
+      *authErrorMessage = "Failed to extract bus name.";
+      return false;
+    }
+
+    USBGUARD_LOG(Trace) << "Extracted bus name \"" << bus_name << "\".";
+    USBGUARD_LOG(Trace) << "Extracting interface name...";
+    const gchar* const /*no-free!*/ interfaceName = g_dbus_method_invocation_get_interface_name(invocation);
+
+    if (! interfaceName) {
+      USBGUARD_LOG(Trace) << "Failed to extract interface name.";
+      *authErrorCode = G_DBUS_ERROR_AUTH_FAILED;
+      *authErrorMessage = "Failed to extract interface name.";
+      return false;
+    }
+
+    USBGUARD_LOG(Trace) << "Extracted interface name \"" << interfaceName << "\".";
+    USBGUARD_LOG(Trace) << "Extracting method name...";
+    const gchar* const /*no-free!*/ methodName = g_dbus_method_invocation_get_method_name(invocation);
+
+    if (! methodName) {
+      USBGUARD_LOG(Trace) << "Failed to extract method name.";
+      *authErrorCode = G_DBUS_ERROR_AUTH_FAILED;
+      *authErrorMessage = "Failed to extract method name.";
+      return false;
+    }
+
+    std::stringstream action_id;
+    action_id << interfaceName << "." << methodName;
+    USBGUARD_LOG(Trace) << "Extracted method name \"" << methodName << "\".";
+    USBGUARD_LOG(Trace) << "Creating a system bus Polkit subject...";
+    PolkitSubject* const subject = polkit_system_bus_name_new(bus_name);
+
+    if (! subject) {
+      USBGUARD_LOG(Trace) << "Failed to create Polkit subject.";
+      *authErrorCode = G_DBUS_ERROR_AUTH_FAILED;
+      *authErrorMessage = "Failed to create Polkit subject.";
+      return false;
+    }
+
+    USBGUARD_LOG(Trace) << "Created.";
+    USBGUARD_LOG(Trace) << "Connecting with Polkit authority...";
+    PolkitAuthority* const authority = polkit_authority_get_sync(/*cancellable=*/ NULL, &error);
+
+    if (! authority || error) {
+      USBGUARD_LOG(Trace) << "Failed to connect to Polkit authority: " << formatGError(error) << ".";
+      *authErrorCode = G_DBUS_ERROR_AUTH_FAILED;
+      *authErrorMessage = "Failed to connect to Polkit authority";
+      g_error_free(error);
+      g_object_unref(authority);
+      g_object_unref(subject);
+      return false;
+    }
+
+    USBGUARD_LOG(Trace) << "Connected.";
+    USBGUARD_LOG(Trace) << "Customizing Polkit authentification dialog...";
+    PolkitDetails* const details = polkit_details_new();
+
+    if (! details) {
+      USBGUARD_LOG(Trace) << "Failed to customize the Polkit authentification dialog.";
+      *authErrorCode = G_DBUS_ERROR_AUTH_FAILED;
+      *authErrorMessage = "Failed to customize the Polkit authentication dialog.";
+      g_object_unref(authority);
+      g_object_unref(subject);
+      return false;
+    }
+
+    polkit_details_insert (details, "polkit.message", "This USBGuard action needs authorization");
+    USBGUARD_LOG(Trace) << "Customized.";
+    USBGUARD_LOG(Trace) << "Checking authorization of action \"" << action_id.str() << "\" with Polkit ...";
+    const PolkitCheckAuthorizationFlags flags = POLKIT_CHECK_AUTHORIZATION_FLAGS_ALLOW_USER_INTERACTION;
+    PolkitAuthorizationResult* const result = polkit_authority_check_authorization_sync
+      (authority,
+        subject,
+        action_id.str().c_str(),
+        details,
+        flags,
+        /*cancellable=*/ NULL,
+        &error);
+
+    if (! result || error) {
+      USBGUARD_LOG(Trace) << "Failed to check back with Polkit for authoriation: " << formatGError(error) << ".";
+      *authErrorCode = G_DBUS_ERROR_AUTH_FAILED;
+      *authErrorMessage = "Failed to check back with Polkit for authoriation.";
+      g_error_free(error);
+      g_object_unref(result);
+      g_object_unref(details);
+      g_object_unref(authority);
+      g_object_unref(subject);
+      return false;
+    }
+
+    gboolean isAuthorized = polkit_authorization_result_get_is_authorized(result);
+    USBGUARD_LOG(Trace) << (isAuthorized ? "Authorized" : "Not authorized") << ".";
+
+    if (! isAuthorized) {
+      *authErrorCode = G_DBUS_ERROR_ACCESS_DENIED;
+      *authErrorMessage = "Not authorized.";
+    }
+
+    g_object_unref(result);
+    g_object_unref(details);
+    g_object_unref(authority);
+    g_object_unref(subject);
+    return isAuthorized;
+  }
+
 } /* namespace usbguard */
 
 /* vim: set ts=2 sw=2 et */
diff -up usbguard-1.0.0/src/DBus/DBusBridge.hpp.orig usbguard-1.0.0/src/DBus/DBusBridge.hpp
--- usbguard-1.0.0/src/DBus/DBusBridge.hpp.orig	2022-08-16 10:24:34.312571194 +0200
+++ usbguard-1.0.0/src/DBus/DBusBridge.hpp	2022-08-16 10:28:33.514545528 +0200
@@ -83,6 +83,9 @@ namespace usbguard
       bool rule_match,
       uint32_t rule_id);
 
+    static std::string formatGError(GError* error);
+    static bool isAuthorizedByPolkit(GDBusMethodInvocation* invocation, GDBusError* authErrorCode,
+    const gchar** authErrorMessage);
 
     GDBusConnection* const p_gdbus_connection;
     void(*p_ipc_callback)(bool);
diff -up usbguard-1.0.0/src/DBus/org.usbguard1.policy.orig usbguard-1.0.0/src/DBus/org.usbguard1.policy
--- usbguard-1.0.0/src/DBus/org.usbguard1.policy.orig	2022-08-16 10:24:34.312571194 +0200
+++ usbguard-1.0.0/src/DBus/org.usbguard1.policy	2022-08-16 10:24:34.311571202 +0200
@@ -1,23 +1,23 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE policyconfig PUBLIC "-//freedesktop//DTD PolicyKit Policy Configuration 1.0//EN"
         "http://www.freedesktop.org/standards/PolicyKit/1/policyconfig.dtd">
-        
+
 <policyconfig>
   <vendor>The USBGuard Project</vendor>
   <vendor_url>https://github.org/USBGuard/usbguard</vendor_url>
 
   <action id="org.usbguard.Policy1.listRules">
     <description>List the rule set (policy) used by the USBGuard daemon</description>
-    <message>Prevents from listing the USBGuard policy</message>
+    <message>Prevents listing the USBGuard policy</message>
     <defaults>
       <allow_inactive>no</allow_inactive>
-      <allow_active>auth_self_keep_session</allow_active>
+      <allow_active>yes</allow_active>
     </defaults>
   </action>
 
   <action id="org.usbguard.Policy1.appendRule">
     <description>Append a new rule to the policy</description>
-    <message>Prevents from appending rules to the USBGuard policy</message>
+    <message>Prevents appending rules to the USBGuard policy</message>
     <defaults>
       <allow_inactive>no</allow_inactive>
       <allow_active>auth_admin</allow_active>
@@ -33,40 +33,41 @@
     </defaults>
   </action>
 
-  <action id="org.usbguard.Devices1.listDevices">
-    <description>List all USB devices recognized by the USBGuard daemon</description>
-    <message>Prevents from listing USB devices recognized by the USBGuard daemon</message>
+  <action id="org.usbguard.Devices1.applyDevicePolicy">
+    <description>Apply a policy to a device in USBGuard</description>
+    <message>Prevents applying a policy to a device in USBGuard</message>
     <defaults>
       <allow_inactive>no</allow_inactive>
-      <allow_active>auth_self_keep_session</allow_active>
+      <allow_active>auth_admin</allow_active>
     </defaults>
   </action>
 
-  <action id="org.usbguard.Devices1.allowDevice">
-    <description>Authorize a USB device via the USBGuard daemon to interact with the system</description>
-    <message>Prevents from authorizing USB devices via the USBGuard daemon</message>
+  <action id="org.usbguard.Devices1.listDevices">
+    <description>List all USB devices recognized by the USBGuard daemon</description>
+    <message>Prevents listing USB devices recognized by the USBGuard daemon</message>
     <defaults>
       <allow_inactive>no</allow_inactive>
-      <allow_active>auth_admin</allow_active>
+      <allow_active>yes</allow_active>
     </defaults>
   </action>
 
-  <action id="org.usbguard.Devices1.blockDevice">
-    <description>Deauthorize a USB device via the USBGuard daemon</description>
-    <message>Prevents from deauthorizing USB devices via the USBGuard daemon</message>
+  <action id="org.usbguard1.getParameter">
+    <description>Get the value of a runtime parameter</description>
+    <message>Prevents getting values of runtime USBGuard parameters</message>
     <defaults>
       <allow_inactive>no</allow_inactive>
-      <allow_active>auth_admin</allow_active>
+      <allow_active>yes</allow_active>
     </defaults>
   </action>
 
-  <action id="org.usbguard.Devices1.rejectDevice">
-    <description>Remove a USB device via the USBGuard daemon</description>
-    <message>Prevents from removing USB devices via the USBGuard daemon</message>
+  <action id="org.usbguard1.setParameter">
+    <description>Set the value of a runtime parameter</description>
+    <message>Prevents setting values of runtime USBGuard parameters</message>
     <defaults>
       <allow_inactive>no</allow_inactive>
       <allow_active>auth_admin</allow_active>
     </defaults>
   </action>
+
 </policyconfig>