Awesome
exploit_me
Very vulnerable ARM/ARM64[AARCH64] application (CTF style exploitation tutorial, portable to other platforms)
(c) B.Kerler 2018-2020
Why:
Some of my friends asked me if I could do some examples of exploitable stuff I've seen in real-world the past years for ARM/ARM64[AARCH64]/others.
So, for training purposes, I thought: Why not :)
Current vulnerabilities:
Level 1: Integer overflow
Level 2: Stack overflow
Level 3: Array overflow
Level 4: Off by one
Level 5: Stack cookie
Level 6: Format string
Level 7: Heap overflow
Level 8: Structure redirection / Type confusion
Level 9: Zero pointers
Level 10: Command injection
Level 11: Path Traversal
Level 12: Return oriented programming (ROP)
Level 13: Use-after-free
Level 14: Jump oriented programming (JOP)
Install on Debian/Ubuntu System:
Download the repo
git clone https://github.com/bkerler/exploit_me
Install needed tools on host (Ubuntu)
~$ cd exploit_me
~/exploit_me $ ./script/setup.sh
Usage hints:
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See hints.txt for a start.
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For trying if it works : *** 32-Bit:
$ ./bin/exploit
*** 64-Bit:
$ ./bin/exploit64
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Example debugging session:
$ sudo ./scripts/disableaslr.sh
(Disable aslr, don't run if you want more fun) (Path dir1/dir2 needed in current exploit directory for Path Traversal vulnerability)
In first terminal:
*** 32-Bit:
$ ./bin/arm exploit [levelpassword] [options] & $ gdb-multiarch ./exploit pwndbg> set architecture arm
instead you can also add architecture in .gdbinit as "set architecture arm"
*** 64-Bit:
$ ./arm64 exploit64 [levelpassword] [options] & $ gdb-multiarch ./exploit64 pwndbg> set architecture aarch64
instead you can also add architecture in .gdbinit as "set architecture aarch64"
*** Example .gdbinit
set endian little #set architecture arm #set architecture aarch64 target remote :1234
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GDB Basics:
Use "si" to step into functions or "so" to step over functions, "info functions" to print all functions, "p [function]" to print function address and information, if symbols exist "b [function]" (Example: "b main" to set a breakpoint and "b *0x1234" to set a breakpoint at addr 0x1234, "c" to continue program, "x/[dwords]x" to print offsets, for example "x/4x 0x1234" and "x/[dwords]x $reg" to print register contents, for example "x/4x $sp". Using pwndbg, you can use "rop" to list rop gadgets, for example "rop --grep 'pop {r3'" to list gadgets which pop values from stack to r3. See https://github.com/pwndbg/pwndbg/blob/dev/FEATURES.md for more details !
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After you've exploited correctly, you will see the password for the next level. So if level2 password would be "Level2": *** 32-Bit:
$ ./bin/exploit Level2
*** 64-Bit:
$ ./bin/exploit64 Level2
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For cheaters or people trying to understand with less instruction knowledge :
See solutions/solutions.txt and source code in src/exploit.cpp
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There are more solutions possible, even with rop chains, not just my example solutions given
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There are some hints printed to console (information leak), which you normally wouldn't have, but these make things easier for beginners, that's why I added it
ToDo:
- Will add other vulnerabilities as I see them or have spare time (like multi-thread vulnerability). But if you want to add some, I'd be happy to provide !
Some referrals to ARM reversing beginners :
- Learn some ARM Assembly Basics and Shellcode stuff over here : https://azeria-labs.com/
- Get Book "Beginner's Guide to Exploitation on ARM" by Billy Ellis and his YouTube tutorial videos
- Read blog "ARM exploitation for IoT" Part 1 - 3 https://quequero.org/category/security/
- Read book "A Bug Hunter's Diary" By Tobias Klein
- Read ARMv8 (AARCH64) Opcode Manual : https://www.element14.com/community/servlet/JiveServlet/previewBody/41836-102-1-229511/ARM.Reference_Manual.pdf
License:
MIT License (Share, modify and use as you like, but refer to the original author !)