Password management

Original author: Tommy Nguyen

Last modified: Mon Aug 1 17:02

Our antipatterns article discusses some insecure things that can be done w.r.t. password from a system administrator or developer point of view. This article is aimed towards users.

There is a wealth of information about there about how to choose a secure password. Often this involves multiple character classes (such as lowercase, uppercase, punctuation etc.) or passphrases (strings of randomly chosen dictionary words, ala Diceware). However, what’s often skipped is the discussion of two other important elements: length and entropy of the password. Without dwelving into a deep discussion, a complex password which is short is weak. And a password with low entropy (that is, the password is generated using a poor random number generator or manually by a human) is also bad. The rule of thumb to remember is that how a password is generated is more important than heuristic measures of the complexity of a password. Furthermore, you should avoid reusing passwords due to credential stuffing attacks.

Regardless of what your password ends up being or how complex your password is, you should be using password manager software to store your passwords. For the desktop, I highly recommend KeePassXC and for mobile Strongbox as KeePassXC does not have a mobile client. You can also use Pass, which is a commandline password store that uses GPG to encrypt your passwords and has a plethora of third party integrations.

Backing your databases up to your phone

We assume you’ve read our iPhone article. A typical mechanism for transferring files to your phone is to either use iTunes or the cloud. However, in addition to iTunes working poorly on Linux, I consider it to be user unfriendly bloatware. I also do not like using iCloud to avoid exposing myself to unnecessary risk.

Transferring your files to your iphone using ifuse is very straightforward:


if ifuse --documents com.markmcguill.strongbox "$HOME"/strongbox/;
    cp "$HOME"/NewDatabase* "$HOME"/strongbox || fail
    sleep 1
    fusermount -u "$HOME"/strongbox || fail

It is a quick operation and you can start using the database on your phone instantly.

Checking your passwords against a HIBP dump provides password hashes that you can use to compare against your password database to see if your passwords have appeared in any breaches. You can either use 1Password’s watchtower feature (read: online, paid service) or compare it offline using KeepassXC. With KeepassXC the command is simple:

keepassxc-cli analyze -H pwned-passwords-sha1-ordered-by-count-v7.txt ~/NewDatabase.kdbx -k ~/NewDatabase.key

Warning: the password file is HUGE and it will take a long time to finish the comparisons.


Isn’t using a single password bad?

Using a single, complex password stored only in your brain is more secure than multiple insecure passwords that you have to remember. Writing those passwords down, storing them in a plaintext file or some other mechanism is not as secure as an encrypted database. It goes without saying that the master password you choose should be long and generated in a cryptographically secure manner.

But your master password can be stolen by a keylogger

The same could be said about any other password, password manager or not. Furthermore, if an attacker has physical access to your computer, it’s generally considered game over. Password managers like KeePassXC do have features like autotype which can autofill passwords in an obfuscated manner to defeat software keyloggers. However, you should be making sure your computer is free of malware anyway.