Questions tagged [shellcode]

A shellcode is a small piece of code used as the payload in the exploitation of a software vulnerability.

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How to change hex to shellcode bytes

0x62, 0x75, 0x66, 0x20, 0x3d, 0x20, 0x20, 0x62, 0x22, 0x22, 0x0a, 0xeb, 0x7c, 0x38, 0x5c, 0x78, 0x34, 0x65, 0x5c, 0x78, 0x32, 0x39, 0x5c, 0x78, 0x31, 0x35, 0x5c, 0x78, 0x39, 0x39, 0x5c, 0xeb, 0x34, ...
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How to revert the output of disassemble (assembly code) to shellcode?

I know is easy to convert shellcode using disassemble tools such as distorm3, etc to assembly codes (00000000: 5c POP ESP), however, how do you revert these assembly codes back to their shellcodes. ...
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when writing 64bit reverse shell in assembly got stuck at createrprocessA api

hello i am writing windows 64bit reverse shell in assembly and after gett connected to the targetmachine ip, i want to create process to spwan a shell, fistly i try to write startinfo struct for ...
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XOR operand type mismatch [duplicate]

I'm trying to get around some input character restrictions by encrypting some data. However, when i try and XOR rbx back to my desired value I get an error stating operand mismatch. Am i missing ...
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How i can get this memory address in Protostar stack 5 CTF

I found this solution for solving protostar's ctf stack5 challenge. The solution works, but I can't figure out how in the stack diagram section we get the address: 0xbffff800 . I understand that NOPs ...
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How To Construct A Shellcode From x64 MASM Assembly

im trying to make a small messagebox shellcode, using masm assembler, im doing so because im not that familiar with other syntaxes, this is the assembly code main.asm: EXTRN __imp_ExitProcess:PROC ...
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Exploit the code calling call_me function + use of shellcode

I need to exploit the following code but not sure how to do it. The idea is to exploit the code trying to call the function which is not used call_me. Second idea is to exploit the code using a ...
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I can get my shellcode to execute when my program is compiled using gcc-3.4(older version), but it doesn't work when compiled on newer versions of gcc

I am on Linux. The hack I am trying get to work is a buffer overflow which overflows into the return address of the program's main() stackframe replacing it with the address pointing to the ...
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How can I exploit a segfault and run a shell command?

Following this: How can I exploit a buffer overflow? I have a code compiled using -fno-stack-protector: #include <stdio.h> void shellcode(){ printf("\n Reached shellcode!"); } ...
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Access violation when executing ShellCode via CreateThread

I Created an executable that contains a Shell code. The ShellCode is suppose to execute calc.exe. I use CreateThread to execute the ShellCode. The Shellcode is indeed executed and calc.exe spawns. BUT!...
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How to print "Hello World" in x86_64 assembly language using stack memory? [duplicate]

I am trying to write a "Hello World" program using stack memory. section .text global _start _start: mov al , 0x01 mov dil , al push 0x0a646c72 ...
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Using buffer-overflow to execute some simple instructions fail -- (segfaults)

I'm trying to buffer overflow and make the make the system execute mmap allocated address which would be a function of some simple instructions, namely mov $0x1, %rax ret the opcode array for this is ...
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Go: Why do processes/Threads started using Win32API funcs seem to hijack and kill the parent proccess?

Now, the following code does what it's supposed to do, load calc.exe to memory and execute it, it does that fine. I've stitched together this code to show CreateThread() Killing my program's execution ...
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Shell does not open when trying to open shell with Assembly code

I am trying to open a shell code using the following assembly code where I have tried to use JUMP CALL POP method. .section .text .globl main main: pushl %ebp movl %esp, %ebp pushl %ebx ...
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Converting a HEX user input to executable HEX and not a string

Scope: I am trying to research on a malware where a ShellCode in HEX is statically declared in a variable. I am trying to make it dynamic so it can work on the same hex but taken from user input. The ...

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