Ecstatic Over Static Passwords

Well maybe not ecstatic but it is pretty exciting that I have been carrying around a way to house a strong static password and didn’t even realize it.

YubiKey

I have had a Yubikey for over a year now and have used it successfully with LastPass. A YubiKey is a handy USB or Near Field Communications (NFC) device that can generate a variety of authentication responses. The default is a One Time Password (OTP) that can be verified via a server running the Yubico software. It is an inexpensive way to provide a two-factor authentication method.

Little did I know, mainly because I don’t always read the instructions, that most YubiCo devices have the ability to hold multiple slots or multiple generators. A slot can be configured to generate the Yubico OTP, a Challenge-response, an industry standard OATH response or it can return a static password generated by you. You press the sensor quickly to activate slot 1 or you press it for more than two seconds to activate slot 2.

The Revelation

Totally missed the part about a static password.

Short static passwords are usually a bad thing but strong static passwords have their place. The best way to use this is to store a strong password suffix on the YubiKey and then you supply the prefix. What you end up with is a strong variable password that most people could not or would not take the time to memorize.

Since the YubiKey allows you to store from 16-64 characters in the static section depending on the model the resulting password could be quite long. The key is configured using the YubiCo Personalization Tool by selecting the Static Password Option.

If you use an 8 character prefix and a 32 character suffix that produces a 40 character password with ease. For example the prefix for your Twitter account may be ‘Blurb2Derp’ and your static key may be ‘ljI10lakhjH_!@#947 *&ghdN1il1li1’.

To use your new strong password type in your prefix then press the sensor for more than two seconds. A password wonder:

Blurb2DerpljI10lakhjH_!@#947 *&ghdN1il1li1

It still will be up to you to generate a total password that has the proper number of security bits and level of entropy. The good point is that you can store the static portion of a password that was generated randomly.

Using this method you could memorize a prefix for each site and use the YubiKey to enter the majority of the password. This would be great for those long TruCrypt passwords that you never can seem to remember. This method may be an issue if you have some sites that disallow special characters or limit your password to 8 characters.

Ecstatic Static

There are several different models of YubiKeys. YubiCo also provides several other authentication methods along with integrations with several major vendors.

Time to go change my passwords.

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