This program lets you do math to numbers. It seems to be more secure then the last: Note the stack canaries; unless we have a leak, we can’t just overflow everything up to the return address. We also can’t jump to the stack. However, notice that this binary doesn’t have PIE enabled, making ROP gadgets […]
This binary gives up it’s restraints in the description: If we decompile the binary with ghidra, we can see it literally just accepts and calls our shellcode. To figure out how linux syscalls work in assembly, you can use this for reference. Just put the correct value in each register then call int 0x80, and […]
This is the first challenge of pwnable.tw. Fitting to it’s name, it requires some basic knowledge of buffer overflows and x86 assembly. First, let’s see what kind of security it has built in: Notice how the stack is executable, and there’s no stack canaries. This will come into play later. We can disassemble the program […]