Hash And Roll Your Way To Secure Passwords

In the electronic battlefield that is 2019, the realm of password security is fraught with dangers. Websites from companies big and small leak like sieves, storing user data in completely unsecure ways. Just about the worst thing you can do is use the same password across several services, meaning that an attack on one gives entry to multiple accounts. The challenge is to generate a unique and secure password for each and every application, and [Ilia]’s way of doing that is called HashDice.

No, it’s not a password manager, or an app – it’s a simple method that can be readily applied by anyone with the right tools. A simple dice is used to create random numbers, which are used to select words from a list to form the basic secret phrase. This is then combined with the name of the service or application to be accessed, the date, and a salt, before hashing using the SHA256 algorithm. The final hash is then truncated to create the password. You can do it all on a device that’s airgapped from the world, ensuring your core secret is never exposed, thus maintaining security.

There are some pitfalls to this method, of course. Many websites make things harder by requiring special characters or enforcing length limits on passwords. [Ilia] helpfully suggests several workarounds for this, but admits that no system is perfect in the face of these obstacles.

If you’re now wondering if your current password is safe, there are ways to investigate that, too.

 

Tearing Apart An Android Password Manager

With all of the various web applications we use nowadays, it can be daunting to remember all of those passwords. Many people turn to password management software to help with this. Rather than remembering 20 passwords, you can store them all in a (presumably) secure database that’s protected by a single strong password. It’s a good idea in theory, but only if the software is actually secure. [Matteo] was recently poking around an Android password management software and made some disturbing discoveries.

The app claimed to be using DES encryption, but [Matteo] wanted to put this claim to the test. He first decompiled the app to get a look at the code. The developer used some kind of code obfuscation software but it really didn’t help very much. [Matteo] first located the password decryption routine.

He first noticed that the software was using DES in ECB mode, which has known issues and really shouldn’t be used for this type of thing. Second, the software simply uses an eight digit PIN as the encryption key. This only gives up to 100 million possible combinations. It may sound like a lot, but to a computer that’s nothing. The third problem was that if the PIN is less than eight characters, the same digits are always padded to the end to fill in the blanks. Since most people tend to use four digit pins, this can possibly lower the total number of combinations to just ten thousand.

As if that wasn’t bad enough, it actually gets worse. [Matteo] found a function that actually stores the┬áPIN in a plain text file upon generation. When it comes time to decrypt a password, the application will check the PIN you enter with the one stored in the plain-text file. So really, you don’t have to crack the encryption at all. You can simply open the file and reveal the PIN.

[Matteo] doesn’t name┬áthe specific app he was testing, but he did say in the Reddit thread that the developer was supposedly pushing out a patch to fix these issues. Regardless, it goes to show that before choosing a password manager you should really do some research and make sure the developer can be trusted, lest your secrets fall into the wrongs hands.

[via Reddit]