Questions tagged [shellcode]

A shellcode or eggshell is a small program represented as a string of instructions in their hexadecimal encoding.

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Shellcode challenge - shellcode works in test program, segfaults in actual binary

Currently working through an introductory shellcoding challenge, and having trouble getting the shellcode to work consistently. I'm working on a 32bit Linux binary. I found this shellcode: http://shell-storm.org/shellcode/files/shellcode-827.php xor…
BronzeOtter
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ShellCode not running as expected - showing segmentation fault core dump

I have already run this command. But my shellcode is not working for me: gcc -fno-stack-protector -z execstack test.c -o test ./test Segmentation fault (core dumped) Here is my shellcode #include unsigned char code[] =…
Alvin567
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Wargames RET2 Systems Shellcoding - Trouble using ```jmp``` instruction to connect parts of shellcode

I am doing the RET2 Systems Binary Exploitation course Wargames (https://wargames.ret2.systems/) and am working on the shellcoding chapter. I am learning about how to use jmp assembly instructions to connect sections of shell code. When shell code…
Aaron
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random address in call instruction

I am trying to use write system call shellcode in assembly but when i run it i am getting a segmentation fault. I did debug it and its because of the call instruction which is having a random address in…
prakash
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How to find a fuction hash when manually resolving in shellcode?

I'm disassembling a shellcode and I found that it resolves adress of some function manually using the hash to find function in kernel32.dll. example : call findKernel32Base .... push 0EC0E4E8Eh call findSymbolByHash mov [ebp-4], eax For this…
Neolex
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Why do we have to put shellcode before return address

I'd like to know why we have to put the shellcode before the return address in a buffer overflow. Logically the return address will point to the shellcode and will be executed. So, the return address should be put before the shellcode. I read about…
Scoobydoo
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