Root me write-up : ELF x64 - Stack buffer overflow - basic

To comply with the write-up rule of root-me.org, in this write-up, I just talk about some hints related this challenge. Here is no solution and correct answer.

This is regular buffer overflow challenge except the architecture.

Because this challenge is based on x86_64, you should be careful calculating related the size of the memory.

Also note that the vulnerable function is not library dependent.

Root me write-up : ELF x86 - Format string bug basic 1

To comply with the write-up rule of root-me.org, in this write-up, I just talk about some hints related this challenge. Here is no solution and correct answer.

The basic of FSB(Format String Bug) is %x. Check the link, it would help you.

Root me write-up : ELF x86 - Stack buffer overflow basic 2

To comply with the write-up rule of root-me.org, in this write-up, I just talk about some hints related this challenge. Here is no solution and correct answer.

The distance is 0x9c-0x1c = 0x80.

The input size of "fgets" is 133.

Function pointer.

Root me write-up : ELF x86 - Stack buffer overflow basic 1

To comply with the write-up rule of root-me.org, in this write-up, I just talk about some hints related this challenge. Here is no solution and correct answer.

The function "fgets" receives 45 bytes input.

The size of array "buf" is 40 bytes.

Root me write-up : Stack buffer overflow basic 3

To comply with the write-up rule of root-me.org, in this write-up, I just talk about some hints related this challenge. Here is no solution and correct answer.

To solve this challenge, there is something to be careful.

Think about Little-endian, The "count++" inside the green box in the photo above, and the location of variables in memory. you can get enough the flag.

Also, since there is an infinite loop, I recommend you to use a debugger to test a payload.