51

MD5 and SHA256 were both designed to be as fast as possible. Their purpose was to compute a hash for relatively big data volumes, e.g. for files. That's why they are very fast, which makes brute-forcing easier. A single GPU can generate ~10^10 SHA256 hashes per second. It is ~10^15 per day. Computing of MD5 is much faster, on some GPUs ~5 times faster. So ...


46

There are a couple problems with this approach. First of all, you're using two plain cryptographic hash functions to hash your data. By themselves, cryptographic hash functions are designed to be fast. That means that it's extremely easy for an attacker to try to brute-force your password. The only time it's safe to use a plain cryptographic hash function ...


18

There are all excellent answers. I will try to address immediate questions. How unsafe would be to publish the hash of my passwords? Very unsafe. Irrespective of the algo used, please never share the passwords or the hash of it on open web. Why: This is a bad practice. A bad habit. You are encouraging yourself and others around you to lower your guard. ...


7

Back in the day when airbags were an expensive option on expensive cars, I used to ride with a colleague who had a BMW-635 with an airbag. He believed he didn't need to wear his seatbelt because the airbag would save him. Nobody believes this any more. Both safety mechanisms are necessary, have complementary purposes Passwords used to be stored in plain text....


5

The answer is cracklib. CrackLib will take the new password and modify it in a lot of ways to see if the modification is the same as the current password, that you had to type before changing the password. So if your old password is acbEFGH123321 and the new is acbdEFGH123321, and Linux complains, it means cracklib took the new password, added/dropped chars ...


3

Quick notes: Typing your password more is bad.This scheme requires you to regularly type your password on internet-connected devices at times you didn't have to before. That opens up additional opportunities for a key-loggers, videos of you typing, a corrupted variant of your script, etc., to steal your password. Fast hashes are easier to dictionary-...


2

No, syncing to cloud isn't MFA. It's syncing. And you are mixing several different things on the same question. On Bitwarden, you have an account. It's the same as having an email account, or a forum account. To access it, you need credentials and have an option to use TOTP. If you enable TOTP, you have MFA - or 2FA in this case. If you needed password plus ...


2

As with pretty much everything that is managed by cloud providers, secrets management as a service is susceptible to hacking attacks, HOWEVER, I would trust Mozilla's and Google's secure secrets management capability and infrastructure security in general much more than keeping those secrets on tools running on my machine. To your last question, all major ...


2

FIPS 140-2 defines standards for cryptographic modules, and related standards specify permitted algorithms which can be validated. Typically, in these environments, the algorithm used for hashing passwords would be PBKDF2, since that's the only approved key-derivation function of that type. For symmetric encryption, you would use AES, and I would recommend ...


1

This is the most salient part: you should change your account password for that website, and also any of your other passwords that are the same as that password. Many people are not security savvy. Some people reuse the same password across multiple accounts. Like both their email and bank accounts. This is what enables credential stuffing attacks to ...


1

Digest authentication is a specific algorithm to do authentication, not a storage method for passwords. So there is no "digest authentication ... instead of ... non-reversible transformation". Comparing one with the other is like comparing streets with cars. Digest authentication requires though to store passwords (or something equivalent which can ...


1

I do not believe Windows stores app credentials by default. But Windows CAN do almost anything you (or an attacker with sufficient access) tells it to. I think it is important to distinguish credentials (your password) and session management (access to the application). These patterns and advice apply to most client-server applications. Applications are ...


1

As a fundamental of security engineering/incident management, if your system is compromised, You must rebuild your system. Because now attacker has enough details about your system. Even if you change encryption key, algorithm, password he still be able to attack again. Because you don't know how he compromise password. If you change password or key, still ...


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