IceDane writes: > Hey there. > > A course in my school involves exploitation of various vulnerabilities, > such as buffer overflows and format string vulnerabilities and so on. > > I'm currently running kbuntu, latest version, which comes with gcc 4.1.2 > stock. If I compile a vulnerable program(A simple strcpy of argv[1] to a > small buffer) and then attempt to execute an exploit, no matter what i > do, it fails. > > I realize that the ubuntu gcc 4.1.2 compiles with the -fstack-protector > as default, however, even if I use -fno-stack-protector, the problem > still prevails. > > All kernels since 2.6 also come with virtual address space randomization > as default, and I've disabled that. > > Anyway, I found something that said if you installed gcc 3.3, you'd be > fine. I try that, and voila, exploit executes accordingly. > > Now, I ask - What is it, other than the -fstack-protector flag, which > can disable buffer overflow exploits like that in gcc? I suspect that the stack layout has changed, and so your exploit no longer works. What happened whan you single-stepped through the exploint injection in gdb? Andrew.
