Everyone must use passwords to protect network resources. The operating system must also protect these passwords by encrypting them using a password hash. Some password hashes are very insecure and can cause immediate vulnerabilities to the computer and network. Other password hashes, like NTLMv2, add new features that help protect the password hash, but if the password is not long enough, the password hash can be decrypted quickly.

It is up to network admins, security pros, and each user to take actions to protect passwords and hashes. Making passwords longer can go a long way to beating these crack tools. Also, eliminating LM and NTLM where possible is a great step to securing the network. Finally, the use of passphrases instead of passwords will instantaneously cripple the current crack tools to where they will never crack a production password.

By Derek Melber at WindowSecurity.com

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