Disassembling MIPS Binaries

Question

I am searching for security vulnerabilities in the firmware of this router, its architecture is mips. I have successfully unpacked the file system. I would like to disassemble the http daemon, located at /usr/sbin/httpd. How can I disassemble this program and run it in spim?

score 5 · Answer 1 · answered Apr 08 '14 at 19:31

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You can give a try to radare2. It has a pretty complete support for MIPS, and provides a lot functionalities to help during the reversing process.

answered Apr 08 '14 at 19:31

jvoisin

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Can you please tell me how? I'm new to reversing. – 0xcaff Apr 08 '14 at 19:39
I have been attempting to use radare2 for MIPS, and it was pretty dodgy (not analysing MIPSEL code, etc.) until I submitted several patches, so use a recent github version – 6EQUJ5 Jun 04 '14 at 05:42

Igor Skochinsky · Accepted Answer · 2014-04-08T21:02:35.280

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I would like to second the suggestion of QEMU.

Craig has a post describing how to debug a MIPS binary running in QEMU using IDA:

http://www.devttys0.com/2011/09/exploiting-embedded-systems-part-3/

(you can also use GDB or another debugger speaking the GDB protocol)

edited Apr 08 '14 at 21:02

answered Apr 08 '14 at 20:44

Igor Skochinsky

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All of these are such good answers I don't know which one to accept! Thank you all for helping me out :D – 0xcaff Apr 09 '14 at 13:50
That's the best answer because it contains link to tutorial. – w s Apr 09 '14 at 14:38

score 4 · Answer 3 · answered Apr 08 '14 at 19:52

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Are you sure that you need spim ?

I'd suggest to use qemu instead of spim for emulation, radare2 for disassembly as @jvoisin mentioned and

retargetable decompiler for decompilation if you really need it.

answered Apr 08 '14 at 19:52

w s

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score 0 · Answer 4 · answered May 03 '17 at 20:28

Regarding the disassembling part, you may want to check JEB (version >= 2.3.0), which provides advanced disassembly and decompilation of MIPS 32-bit code.

The MIPS debugger is only available for Android Linux though, so you won't be able to debug your program using this tool.

There is a demo available on PNF Software's website.

Disassembling MIPS Binaries

4 Answers4