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ubertooth-rx - Classic Bluetooth discovery, sniffing, and decoding


ubertooth-rx [ -l <lap> [ -u <uap ] ]
ubertooth-rx -z


ubertooth-rx(1) is the primary interface into Classic Bluetooth (BR) functionality provided by Ubertooth. It has two main modes of operation: piconet following and survey mode. In either mode, ubertooth-rx(1) is able to discover undiscoverable devices. See [DISCOVERING UNDISCOVERABLE DEVICES][].

In piconet following mode, the tool will follow the first piconet it fully identifies. In survey mode the device will attempt to identify all piconets in a given area and display them after either a timeout or manual interruption.

Piconet following is the main mode entered when no arguments are passed to the command or a LAP and optionally a UAP are provided. If no arguments are passed, the tool will attempt to calculate the UAP for any observed LAPs. If a LAP is passed, the UAP will be calculated for that specific LAP. Once a LAP and UAP have been recovered, the tool will attempt to recover the clock value, and if that succeeds it will follow that piconet.

Survey mode, entered using -z, will record all LAPs and attempt to calculate the UAPs for any observed LAPs. This mode can be combined with a timeout using -t, and it can be interrupted at any time using ctrl-C.


Follow the first piconet whose LAP, UAP, and clock are recovered from the air:


For a given LAP, calculate the UAP and recover the clock, then follow:

ubertooth-rx -l 112233

For a given LAP and UAP, recover the clock then follow:

ubertooth-rx -l 112233 -u ab

Enter survey mode for 20 seconds, and print out the BD ADDRs of all observed piconets:

ubertooth-rx -z -t 20


Major modes:

-l <lap> : Limit UAP recovery, clock recovery, and piconet following to a given LAP. Format is 3 bytes / 6 hex characters.

-u <uap> : Limit clock recovery and piconet following to a given UAP. Must be used in conjunction with -l. Format is 1 byte / 2 hex characters.

-z : Survey mode: recover all LAP and UAP pairs and display them. Will run indefinitely until interrupted with ctrl-C unless paired with -t.


-i <input> : Input file. If not specified will perform live capture using Ubertooth.

-c <0-79> : Fixed channel for all major modes. If not specified will sweep through all channels.

-e <0-4> : Maximum access code bit errors. [Default: 2]

-t <seconds> : Timeout in seconds. If not specified will run indefinitely. Suggested values for -z: 20-60 seconds.

Output options:

  • -r <file.pcapng> : Capture packets to PcapNG
  • -q <file.pcap> : Capture packets to PCAP
  • -d <file.bin> : Capture packets to binary file suitable for use with -i.


-V : Version information

-U<0-7> : Which Ubertooth device to use


Classic Bluetooth piocnets are defined by the Lower Address Part (LAP) and Upper Address Part (UAP) of the master device. These are elements of the master device's Bluetooth Address (BD ADDR).

Consider the following BD ADDR:


The lower address part (LAP) is the lower 24 bits, so 88:AA:BB. In the context of this tool, the value is written 88AABB. The upper address part is the next 8 bits, so 66. The 22:44 is called the Non-significant Address Part (NAP) and as you might imagine it is not significant.

In piconet following mode, the tool will recover LAP values from the air and attempt to calculate the UAP from those. It will go on to follow the piconet if it can recover the clock value. In survey mode, the tool will simply recover LAP and UAP values.

To convert LAP + UAP pairs back into Bluetooth addresses, do the reverse of the above. For example, if the tool recovers a LAP of 36A2B4 and a UAP of 98, the associated Bluetooth address is ??:??:98:36:A2:B4. Any value can be substituted into the ?? slots and most Bluetooth tools will still work. For example, hcitool name 00:00:98:36:A2:B4 will establish a connection to the device and return its name.

This attack works against discoverable and undiscoverable devices alike.


ubertooth-scan(1): active device scanning and inquiry using Ubertooth and BlueZ

ubertooth(7): overview of Project Ubertooth

D. Spill and A. Bittau. "BlueSniff: Eve Meets Alice and Bluetooth." USENIX WOOT 2007.


This manual page was written by Mike Ryan.


ubertooth-rx(1) is Copyright (c) 2010-2017 Michael Ossmann, Dominic Spill, and others. This tool is released under the GPLv2. Refer to COPYING for further details.
March 2017 Project Ubertooth