Now that this issue has been fixed, I wanted to disclose a security problem that affected the Heroes of Newerth login servers. For background, the Heroes of Newerth login protocol uses the common authentication protocol known as SRP6 (for more info, see: http://srp.stanford.edu/index.html). However, there was a fatal omission in the login server code which essentially allowed any password to be accepted. I was able to use this to login to staff and GM accounts at will.
The flaw is a mathematical one. From the SRP6 spec:
If the host fails to check that A mod N != 0, and an atta