Download Security Threats and Countermeasures in Bluetooth

with them. The PIN codes for Mentor and Belkin printer adapters are "1234" and "belkin",
respectively. Each of these so-called "secret PIN codes" can be easily found in the printer
adapter manual, which can be freely downloaded from the Internet.
Because all four printer adapters have either default or fixed PIN codes, all Bluetooth-enabled
devices that are using them via an encrypted link must also use the same PIN code í
otherwise printing is not possible. Moreover, all four printer adapters are class 1 Bluetooth
devices with enhanced sensitivity levels (see Section 2.3), making long-distance attacks
against them possible.
In our practical experiments we used a USB printer with a Bluetooth USB printer adapter as
the Bluetooth-enabled printer, a laptop running a Frontline FTS4BT [Fro08] protocol analyzer
(see Chapter 5) with one Bluetooth 2.0+EDR compatible USB ComProbe as the attacking
device, and a Bluetooth-enabled laptop (Bluetooth 1.2 compatible) as the legitimate
Bluetooth-enabled device that was using the printer. Frontline FTS4BT v6.10.4.0 software
[Fro08] was also used in our practical experiments.
Our Bluetooth security analysis tool works in the following way: [Haa07b]
1. All information that is sent to the Bluetooth-enabled printer is intercepted by using a
Frontline FTS4BT protocol analyzer. If the intercepted data is encrypted, it is
automatically decrypted by the protocol analyzer.
2. Intercepted raw data is exported to a comma-separated ASCII text file (see Figure 23).
3. The ASCII text file is parsed in such a way that only payload coded in hexadecimal,
i.e. the actual intercepted user data, will remain, as shown in Figure 24.
4. Hexadecimal values in the parsed ASCII text file are used to produce the original
printed binary file that was sent earlier to the printer by the Bluetooth-enabled device,
i.e. the file produced contains the same information as the file that the user can
produce, for example, using her printer's standard "print to file" feature.
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