It’s all over the news: a vulnerability has been found on OpenSSL that leaks memory contents on server and clients. Named Heartbleed, it has a very simple patch and some informative posts have already been written about it (Troy Hunt, Matthew Green).
What nobody is saying is that the real root cause is the lack of modern memory management in the C language: OpenSSL added a wrapper around malloc() to manage memory in a more secure and efficient way, effectively bypassing some improvements that have been made in this area during a decade; specifically, it tries to improve the reuse of allocated memory by avoiding to free() it. Now enter Heartbleed: by a very simple bug (intentional or not), the attacker is able to retrieve chosen memory areas. What was the real use of that layer?
Face it: it’s a no-win situation. No matter how many ways these layers are going to be written, there will always be a chance for error. You can’t have secure code in C.
But re-writing and/or throwing away thousands of security related programs written in C is no-brainer: the only way to securely run these programs is with the help of some memory debuggers techniques, like those used by Insure++ or Rational Purify. For example, the next technical report contains a detailed analysis of some of these techniques that prevent these kind of vulnerabilities:
