episode04

Episode 4 - Finding Buffer Overflow with Fuzzing

We found a crash with afl, but it turns out to be a bug in the argv-fuzz-inl.h file.

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Commands

This project builds iteratively on the previous episodes. In this episode we found a buffer overflow issue in argv-fuzz-inl.h, which we can fix by checking the rc counter cannot count too high.

while (*ptr) {

    // fix buffer overflow
    if(rc >= MAX_CMDLINE_PAR) {
      break;
    }
    
    ret[rc] = ptr;