Unchanged default access passwords are a pervasive problem in computer security. A recent high-profile example is the Mirai botnet that spread by using 61 common default login credentials.
In programs using crypto, passwords are often used to generate cryptographic keys. For example, they are used to generate the “key encrypting keys” that are used to protect private keys stored in keystores, or the master key used to protect persistent application data written to storage.
Unfortunately, these passwords are susceptible to the same problem: they have de facto “default values”, often coming from HOWTOs for setup. For example, the password “changeit” figures in several guides for configuring TLS private keys for Java web applications. We trace these passwords using our Analyzer tool, and we encounter a substantial number of “changeit”s in the wild.
Sometimes default crypto credentials are even easier to exploit. In the recent Primefaces bug, many applications were using the default password (“primefaces”) to generate the encryption key. This would lead to secret values encoded in encrypted URLs being leaked, and unlike access passwords, there would be no log to show that attack was being made.
Application frameworks can sometimes make it unnecessarily complicated to change default passwords, but still there’s little point encrypting if the password is unchanged. Our Analyzer tool checks crypto passwords against a dictionary of known defaults and common weak passwords.