YubiKey-Guide VS naive-hashcat

Instead, most people generate keypair(s) on an airgapped machine and write them to two Yubikeys. Or write subkeys to a single Yubikey and keep a backup in encrypted form. See https://github.com/drduh/YubiKey-Guide

I'd recommend using the Yubikey as a GPG smartcard[1]. The private key stays on the Yubikey. I also use it for ssh. But make sure you have a backup key or two, just in case the primary Yubikey gives out. FIDO2 and all other regular Yubikey functionality still works with it.

[1]: https://github.com/drduh/YubiKey-Guide

The excellent guide by drduh should be mentioned here: https://github.com/drduh/YubiKey-Guide — I've been using this approach for years to store my OpenPGP keys on Yubikeys and use them for SSH.

I don't generate my keys on devices. That lets me be flexible and keep backups, as well as use the same keys on multiple physical devices. Using a single yubikey is a bad idea, as you're bound to eventually lose it or break it. Hasn't happened to me yet in 5 years, but I expect it to happen.

I followed this guide to generate a master key and three subkey.

See https://github.com/drduh/YubiKey-Guide . Also google for OpenPGP card specifications, they will answer your question

Regarding GPG/SSH keys, there is a great howto: https://github.com/drduh/YubiKey-Guide

I'd be lying if I said I understood all of that. I'm definitely going to do some research ahaha. Someone else on this post sentence this like which they said was very good guide. https://github.com/drduh/YubiKey-Guide

When storing the key on a Yubikey, however, all you need is just the PIN in order to use the key. It can contain numbers, letters, symbols, etc. and can be quite long, so you can treat it as a passphrase for all intents and purposes. There are actually two PIN codes: one regular one, for a read access, and another administrative one, for write access for when you want to modify the gpg applet settings or the key on the Yubikey. There is also a limit to how many times in a row you can enter pins incorrectly, after which the gpg applet gets locked and the only thing you can do is reset it, erasing the PGP keys. See https://github.com/drduh/YubiKey-Guide for more information.

Try follow this guide from DrDuh https://github.com/drduh/YubiKey-Guide/blob/master/README.md

For this, I downloaded wordlists such as the rockyou wordlist and used tools such as Hashcat and John the ripper.

For decrypting the .cap file, we've different techniques. We'll use simple technique using aircrack-ng only. It'll help us crack the password using a wordlist. You can use rockyou.txt wordlist which is most commonly used & is updated on regular basis.

First, any sort of password that uses an actual word (English or otherwise) has a far greater chance of being cracked. This is due to the fact that common password lists (e.g. the rockyou list) contain millions of unique entries from sites around the web. Many people share a favorite animal or plant as well, so unless your favorite animal is something unique like Mustela erminea there's a good chance that it's an entry in a list somewhere.

Most of the time a DB of hashed passwords is leaked/stolen and the attacker has unlimited attempts to brute force that. What's also commonly done is that they run it against dictionaries (and there are some pretty good dictionaries for that and some of them are easily accessible online) and if the DB is large enough, they're practically guaranteed to get hits immediately.

Looking at the GitHub page for naive hashcat, it appears as though it only takes at most three arguments. Is there a reason you're using it over regular hashcat?

First, it is important to know how the process works. Hashing is a process essentially different from encryption - you can only do it once. It means that we cannot really recover the plaintext of a hashed password; instead, we can only compare its hash with our guesses. So, it's like hashing several words and seeing which of them matches exaclty our hash. Then, it must be the password. We can automatize this process with two tools: hashcat and a dictionary of potential passwords. This kind of dictionary is easy to find on internet, so we are going to use rock you.

I use only SecLists (https://github.com/brannondorsey/naive-hashcat/releases/download/data/rockyou.txt)

rainbow table ("dictionary") plaintext or broken list of common passwords (i.e. Rockyou) leaked from many sources ^ those give you an idea of what people think are "clever" passwords

It's important to choose strong passwords. That's because there are lists of millions passwords like rockyou.txt which can be used to brute force your Linux system using hydra.