\documentclass{article}\usepackage{charter}\usepackage{hyperref}\begin{document}\section*{Homework 3}\begin{enumerate}\item What should the architecture of a network application under Unix be that processes potentially hostile data?\item How can you exploit the fact that every night root has a cron job that deletes the files in \texttt{/tmp}? (Hint: cron-attack)\item How does a buffer-overflow attack work? (Hint: What happens on the stack.)\item Why is it crucial for a buffer overflow attack that the stack grows from higher addresses to lower ones?\item If the attacker uses a buffer overflow attack in order toinject code, why can this code not contain any zero bytes?\item How does a stack canary help with preventing a buffer-overflow attack?\item Why does randomising the address where programs are run help defending against buffer overflow attacks?\item Assume format string attacks allow you to read out the stack. What can you do with this information? (Hint: Consider what is stored in the stack.)\item Assume you can crash a program remotely. Why is this a problem?\item How can the choice of a programming language help with buffer overflow attacks? (Hint: Why are C-programs prone to such attacks, but not Java programs.)\end{enumerate}\end{document}%%% Local Variables: %%% mode: latex%%% TeX-master: t%%% End: