![]() Before, with simple hashing, if one hashed password was cracked, all the other passwords with the same value will also be cracked. Now this becomes more difficult as the same password is likely to produce a different output. ![]() Unfortunately this is weak from both a dictionary attack and brute force, so we add some salt: These days MD5 and SHA-1 are seen as weak for many reasons, so we often start with SHA-256 (which produces a 256-bit hashed value) : Unfortunately technology has moved on since the creation of hashing methods, and they can often be easily cracked using brute force (where an intruder keeps hashing values until the output matches the hash) using a dictionary of common passwords, or use a rainbow table (which has a pre-compiled list of hash values). There are four core concepts in cryptography: public key encryption (asymmetric encryption) private key encryption (symmetric encryption) one-way hash and encoding:Īll of the methods above allow for the easy reverse of the encryption or encoding process if the key is known, apart from one-way hashing where it should be almost impossible to reverse back the hashed value to the original data. We can add salt, but if the intruder gets the salt, they can try popular passwords.Ĭomputing power, too, is increasing massively, especially around parallel processing in the Cloud, and with GPU Graphics cards (which can have over 4,000 cores, each capable of try a range of hash values). With hashing methods we often want to slow things down, as we want to stop an intruder from brute forcing the hash (where they try a wide range of passwords). Generally we have moved from running cryptography on hardware to software implementations. In cryptography we like things to be fast in order that we can process things in real-time. The penalty is that it is slower to hash, so there a sweet spot, but with computing power vastly increasing in the cloud, every crypto method needs a bit of slack! In fact, if I increase to 31 it is over 33 million times more difficult (2^25). ![]() it is over 1,000 times more difficult to crack. With Bcrypt we get a number of rounds for the hashing, so if I increase the number of rounds from 6 to 16. Many organisations think they are safe as they use salted passwords, but they are not if they use weak passwords. The passwords themselves are hashed version, but these are fairly easily to crack with rainbow tables, especially as users tend to pick weak passwords. Now, a dark web market dealer - The Real Deal - has been offering these account details for 5 Bitcoins ($2,200). ![]() In 2012 Linkedin was hacked, and there was a leak of 6.5 million usernames and passwords, but this has risen to 117 million. If the salt is kept with the hashed password, as most systems do, the weak passwords which come from dictionaries would have been easily cracked. While this is true, the shocking truth that the passwords themselves would have been cracked even with salting. In particular, LinkedIn failed to adequately protect user data because it stored passwords in The $5 million class action, in 2012, against LinkedIn outlined: If the salt is stored with the hashed value, it is of little use with easily guessed passwords. You don't have to be Eve The Magician to realise that if I tell you that my password is "qwerty", and you take a hash signature of it to get: "B1B3773A05C0ED0176787A4F1574FF0075F7521E", and then I tell you I've used a salt value of "64gfc*w", and you quickly take a hash of "64gfc*wqwerty" and get: "DAA903ACDA75D0FEDDEFED1FE39825EDB42D9991".
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