![]() ![]() ![]() On a little endian system, values are represented by the least significant byte first. After that it runs our second argument through the validate_passwd function: /* WARNING: Function: _x86.get_pc_thunk. On a big endian system, you would not represent the data in little endian. So we can see that it checks to ensure that argc is 3 (which means two arguments in addition to the file name). Do integer overflows also buffer overflow Hi, I'm currently learning about c and the classic vulnerabilities that arise. * WARNING: Subroutine does not return */ In this case, a buffer is a sequential section of memory allocated to contain anything from a character string to an array of integers. When we take a look at the main function in Ghidra, we see this: /* WARNING: Function: _x86.get_pc_thunk.bx replaced with injection: get_pc_thunk_bx */ A buffer overflow condition exists when a program attempts to put more data in a buffer than it can hold or when a program attempts to put data in a memory area past a buffer. It tells the compiler how to treat the variable. When we run it, we provide input via two arguments to the process. The 'data type' of a variable is only relevant in source code (and even then only in some languages). So we can see that we are dealing with a 32 bit binary with no PIE or Stack Canary. Integer overflow can lead to buffer overflows and the execution of arbitrary code by an attacker. '/Hackery/pod/modules/integer_exploitation/int_overflow_post/vuln' Vuln: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux.so.2, BuildID=b0d1dbf76b9c7c6ae45ab201775536d7b7096b2d, for GNU/Linux 3.2.0, not stripped ![]() Let's take a look at the binary: $ file vuln Objective of this challenge is to call the win function. ![]()
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