Password Cracking - Computerphile
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- Опубликовано: 21 сен 2024
- 'Beast' cracks billions of passwords a second, Dr Mike Pound demonstrates why you should probably change your passwords...
Please note,at one point during the video Mike suggests using SHA512. Please check whatever the recommended process is at the time you view the video.
Here's a look at 'Beast': • BEAST & The GPU Cluste...
How NOT to Store Passwords: • How NOT to Store Passw...
Password Choice: • How to Choose a Passwo...
Deep Learning: • Deep Learning - Comput...
Cookie Stealing: • Cookie Stealing - Comp...
/ computerphile
/ computer_phile
This video was filmed and edited by Sean Riley.
Computer Science at the University of Nottingham: bit.ly/nottscom...
Computerphile is a sister project to Brady Haran's Numberphile. More at www.bradyharan.com
My password is unbreakable because I'm using my name followed by the digits of pi. All of them.
an unending password? youre gonna crash the db~ space limit
clever boy
Well not hashable. Nice try
Big brain time
big brain
Q: What are you using the graphics card for?
A: Well -- terminal apps.
"We don't store passwords unencrypted in a database because that's a terrible, terrible idea."
You would be surprised.
Facebook XD
@@mohnishkumar i was going to reply that too XD
@Kappa Chino thought so too. Hashing is irreversible.
Password Managers
RacingAtHome the more you know
""iloveyoukate" 14:46 he's risking his accounts for you kate. I hope you guys didn't split up 😂
I was going to comment the same thing
that guy was not keeping password for sure. he was feeling emotional while doing whatever he was doing. Emotions = Hacked.
Kate doesn't even know he exists.
It is Kate herself, advised by some shrink.
The "iloveyoukate" virgin vs the Chad "freakpower1"
computer took about 1 second to look through about 40,000,000,000 hashes
10:13 human took about 1 second to multiply 26 times 2
Well, that's not a very fair comparison, is it? Computers are, at their core, all made for mathematical functions. Humans, on the other hand, are not. When it comes to "close enough," humans are generally better.
@@uniqueusername_ Oh really? I thought i could run through a 40bil database that is stored in my head. *Heavy sarcasme.*
Remember it was built by human
uniqueusername_1024 R/FUCKINGWOOOOOOOOSH
@@uniqueusername_ r/whoooosh
Password dictionary:
1. password
2. user
3. correcthorsebatterystaple
@@rabbabansh I am not and I don't get it.
Wow
hunter2
my password: J1bbbbberb0y418
You would be surprised at just how crappy the average password is. There is a reason websites force users to use passwords of minimum length with letters numbers and sometimes symbols. Router admin passwords tend to almost always be default. When they're not, it's usually very easy to guess. Luckily? in my area, the local ISP supplies routers/models with random passwords by default, but they are listed on the underside of the router/modem. Gain physical access to the router, you can get the credentials. If you have no physical access, I guess it's secure enough.
I'm surprised that Tobey Maguire knows this much about hacking...
I thought he was Elija Wood
Well you see... After he lost the role as Spiderman, he had to get a new job. So he became Hackerman :)
He did stay a long time on the web though
sirdeakia
Underrated comment. Why didn't people get this? It's gold.
I know for sure in that bag with the english flag there's his Spiderman outfit!
It would be interesting to revisit this topic and see how things have changed in the past 6 years.
Can you suggest me any such videos
For one thing the 4x Titan X GPU he has are are roughly equivalent to an RTX 4070 which is a ~$700 GPU. The modern equivalent of his system (say 4x 4090) is around 50 time faster than his system.
Wait really? @@mully006
that awkward moment when you see your password...
shhhh
which one was it?
Do you love Kate too?
Lemme guess qwerty ? Lol
siksreik heh heh. I saw that
Love this guy. He should be teaching.
+Max Musterman he does, at The University of Nottingham ☺️
That's it, I'm transferring.
Agreed.
Paused the video just so I would say the same thing!
Not to mention right here :)
Just for your information, the "Beast" machine may be fast for a regular home user, but it is incredibly underpowered compared with a server-grade solution for compute workloads.
Imagine several racks of servers with 4 cards each. Those are available out there, and regular people can build them too with the right amount of money, or rent time on them for relatively cheap
I love how the videos have this 'unscripted' feel and they feel like they're real conversations
Really good video dude. No silly music or fast cuts and no annotation spam on the screen, subscribed.
I think a lot of video editing courses encourage people to do the music thing. Dude I am hear for the data above else. Not the music. It gets distracting. Even with a lot of gamer videos. I can not stand it.
You are trying to focus on the tactics and insights. Like studying with the music blasting. Sometimes it helps, but often it is a distraction.
photographer
Bruh just create a python script that encrypts an input and since only you have this encryption system it's very safe
That's why a lot of websites require you to have a special character and a capital letter. The most common way of doing it is capitalizing the first letter and putting the special character at the end though
@@Dtr146 How did you know my passwords!?
Back in the day, this video (along with your "how to choose a password" video) taught me a huge amount. I think an update could be very valuable for many people. It seems that Lastpass recently lost password vaults for millions of people, which I think will create a lot of interest in this subject.
Mike: "So if your password is 6 characters long, its being cracked right now, and its being cracked quickly"
Me:
🤣🤣🤣
What's your password?
thanks just bought some pizza pans from amazon
My password with 6 characters: *sweating profusely*
My password with 31 characters: *hah, mere mortals.*
My password is 7 characters long, so take that hackers.
my password is L1pZ7z3qy so it's pretty secure, nobody gonna find out
All I see when you enter that is a string of asterisks
Thanks for the revelation.
👌no one will ever now this passwords
if u enter ur credit card number it gets blocked see
**** **** **** ****
@@realszn here's all the number present on my card 54120
So you're saying pA55w0rd is not a good choice?
Michael Burke no, try password123
123456 takes the longest to crack
99999 or zzzzz depending on the algorythm
*hacker voice*
I'm in
10^6 combinations (?)
kate i think your boyfriends pass is hacked
yeah lol
Oh no not his boyfriend's.. His secret admirer's
+Attila U Random characters letter and symbols. around 30+ of them.
+Attila U well I was in a house were the password was something like this: 9684263675467468447836794598211636063674678
only the length is the same but I think it is hard to crack
Mine is something like this
5927592058295712395736189037483194721948271930183
49 random digits.
Now I kind of want a video about Lastpass or Dashlane and how these password manager are secure (or not). Seems like the logical follow up.
I watched a video from DefCON about this sorta thing and actually they are a 2 edged sword. They are bad because then all the attacker has to do is get your database file or hack your password into the password manager, and good because they prevent keyloggers from getting passwords.
treahblade I guess so
If you use Keepass then you don't have to worry about external security. Only your own files on your own computer. And you need 1 password to be secure. That's it.
I've never used a password manager, it seems illogical to have all your passwords behind one password. And where do you store the master password without needing _another_ password?
Yep
this video made me change my password in all my social media accounts, and bank accounts, online games, buy a new house, move to a completely isolated planet and use encrypted network connection that runs through several illegal VPN networks. I am now living happily here in Mars. Thanks.
Nice
I know this is a joke comment, but using an illegal, an "untrusted", VPN is a TERRIBLE idea. You could be feeding your Computer Information to Cyber Criminals by connecting to an Untrusted VPN.
Something worth thinking about for those wanting to go the Cheap/Free route for VPNs.
*Thanks_Turnercyber🙏*
A lot of people think "I'm going to go onto some website and test how strong my password is"... Those people are having their password stored away in a database to be added to someone's password dictionary.
Either that, or some other third party injected Javascript into the page.
You can use Fiddler, Wireshark, or your browser's network inspector to see if any web requests are being sent out.
Which is why I don't use those websites for obvious reasons.
there's a password in my head that I never use lol
Yes.
when websites ask for passwords and force you to fit narrow criteria like "must be between 8 and 12 characters and must contain at least 1 number (with no repeating adjacent numbers) and must contain at least 1 capital and 1 special character" are just reducing the search space for hackers.
but isnt that putting in more variables for computer to check making it harder?
Not really as like he said it relies on use of common words so if your use zWq0£jL3s, there is no logical combination this would occur in words
But If I'm cracking these then I know that
1) I can skip all passwords under 8 and over 12 characters
2) I know that all passwords will have a number so I don't need to try any passwords that don't have them
3) same for capitals and special characters
This comment was aimed at thunderbolt my bad.
There are more combinations of passwords with 8 letters than there are from 1-7 combined. Forcing at least 1 number also increases combinations from 26^8 to 36^8.
"Forgot my password"
"You're receiving this e-mail because you've clicked on 'forgot my password' on our website. Here it is in plain text for anyone to see. Your password is: JustCheckingIfThisWebsiteStoresPasswordsProperly"
That's pretty clever right there. Now I have to try doing that. Thanks
Pausing at 16:38
ma man had a freaking HEX Code as a PW and still got cracked.
ahahhahahha damn this guy is so funny and smart. mad respect to u mike.
RIP, that’s rough
That's not a hex code he set as a password. That's just the program not being able to display the special characters. If you convert the hex code to to ASCII, the password is "kindé"
@@gchcom6902 oohh thanks for that.
That doesn't seem like it would be very hard to crack. The character set is just 16 characters. If the person thought he was being clever, there's could be 10 million people who had the same idea and the cracking software has seen it all before. It's probably not much harder to crack than 12345678.
I just assume I'm never going to come up with some clever password trick that at least 1 million human beings haven't already thought of.
@@gchcom6902 My guess would be kindé (using utf-8)
I just love this! not only because there's no chance my password will be found, but because even the most hardcore IT dudes in my area (including 2 schools I worked at) use horrible passwords, to secure thousands of pupils' social security numbers etc. At my first job, I demanded that the passwords got changed, or I would not work there as i'd be targetted for irresponsible care, in case we got hacked. Sadly they refused to change and I quit my job.
Smart move.
5:18 "MD-5 should not be used by anyone ever, EVER again."
Meanwhile, in the Yahoo's headquarter...
Amusing.
I'm dying 😁
Could you help me understand? Was he just checking to see if he could guess the LinkedIn pass words that were stolen? Im trying to understand how this would work for an actual site, because after you try the wrong password several times, you get booted, or blocked, and the user gets notified. How would this actually work? Are they taking these passwords and entering them against a live site? If that is the case wouldnt the hacker get blocked after a few seconds? Plus with 2FA, is this even relevant?
Ronin Ryu are you serious? 😂😂😂
Nils Svanstedt yes I’m serious asshole
ANyone else burst out laughing when they saw someone had used ganjagoblin as their pass?
Your icon almost got me there damn.
it always get me. the worse is the fly one, I don't know if you never saw that, but *DAMN* each time I try to swipe the screen like a fool
+Russell Teapot The spider is facing 45° left, I don't get how it can startle anyone ever since scrolling means it moves upwards diagonally. Won't judge though :/
Well I wasnt scrolling when I was reading the comment but yeah once I scrolled I realized it wasnt real :/
did you see "iloveyoukate" at 14:49?
14:47 'ganjagoblin'
best password ever, even if it shows up on the cracked list 😂
420
Ganja means bald in hindi, so might be the reason
I cracked up when camera focused on that on screen - glad you highlighted it 😀
@@Gamer-uf1kl it also means weed or heroin, not sure which one.
@@arpitpatel5312 cannabis/marijuana
This guy is my fav Computerphile guy
Amazing how far computer processing has come in the past 20 years. I remember messing about with brute force hashing on an i486, and it took forever.
I didn't know Peter Parker was a damned hacker.
I have a theory: in this Alternate Spiderverse, Peter Parker (by Tobey Maguire) got fed up with chasing low-budget criminals in NY, quit his cr*ppy job and moved into the UK. There he developed an English accent, got a degree (and later a PhD) in cybersecurity to protect his new identity and since he already had close relations with the Web ;) So, this would be the origin story of Dr. Mike Pound
@@usseal922 Ha I only had to scroll 5 comments to get to here. This makes the op fact.
i cant unsee that now
I thought he did web design
Lol
15:35 "Now luckily, these leaks happen all the time" Interesting... choice of words ;)
He's telling how to crack passwords, what do you expect?
Also that smirk on his face when he said dive
That might be his hacker name
Cause its getting more exposure...
You probably DONT want to test your passwords strength on online services that claim to only tell you how good your password is. While most of those services are probably safe to use, you can never know what service is also making it's own little (or huge?) dictionaries with just the awesome and secure passwords you give them to "test" for you.
solution: disconnect from the internet before you type your password and close the tab before reconnecting
Theoretically still insecure
Ein Frosch~ howsecureismypassword.net is save. Its fully written in Javascript and you can look for the code yourself
Best passwords are sentences like "cow curry diagram!2n;"
What you have to realize. Is that the longer and more complicated your password is. The harder it is for a computer to compromise. Given enough time, energy, and technology. All passwords are easy. Each time an encryption standard is compromised. You migrate to something else. It is a never ending race.
11:41 he just dodged that pop up
Dude.
Dude.
i dont get it ._.
That's pretty meta!
@@brunosteffen8173 The card at the top right pops up at the same time as he moves his head away from it
Really amazing video and quite informative even for curious dummies like me! Honestly it's just fun to watch the guys talk about their passion and learn a little even if i don't get all the details, but it's worth the effort to understand a little more about the technology we all live with.
You can think of "hashing" algorithms, like MD5 or SHA512, as being a secret decoder ring, like the ones you used to get in a box of Alpha Bits, only a bit more sophisticated.
Fantastic video! Loved it :-) Good to know i am doing my passwords right, different one for every site too!
omg its a wild xisuma comment from 8 months ago!
LOL i love scrolling through random videos comments and just finding a Xisuma comment with only 5 likes (make it 6)
Nice to know that Xisuma watches the same videos as me xD
Wow, I keep seeing you on a lot of videos... lol
Morten lol same
You keep following me around everywhere I go!
14:42 "I love you Kate" aww
@@Big_Tex xD
cute
@@Big_Tex and now it's: KateTookEverythingFromMe
Unterarzt update: its how kateijustwantthekidsbackplz
14:18 "I love you Ivan"
14:48 "ganjagoblin" lmao
marcuslola Thats my password
420 blaze it.
hahahahahahahaha
I am now changing my password to "ganjagoblin"... consequences be damned!
bro I caught that too - had to left arrow to confirm lol
Fun fact: The odds of you picking the same password as another guy are HIGHER than picking a username that already exists.
not if my passwords look like siUn$2$8’clwo!&/ienzla!!:&*’eisnJbdKbs&29,£~*£\’Idk&/9
@@Jay-S04 That's been added to the dictionary now
@@Jay-S04 i use keepass, do mine look like that
Not a fact, but closer to a hypothesis
This is why Peter wasn't allowed around computers.
An update for those of you who are watching this now - I don't know if this wasn't the case back then, but nowadays you use a hash algorithm that is slow by design, like Bcrypt, so that attackers are limited by the speed of the algorithm rather than exclusively by the grade of their hardware.
The best hashing algorithm: Google Translate!
Make your password a wikipedia page google translated a dozen times.
RandomCatDude wouldn't work, they update the algorithm too often, those cheeky bastards
No man Google translate just translates
@@randomcatdude only 12times do it 100+times
a dozen of something is 12 of something
Dani Jensen I think everyone knows what a dozen is
I've learned (or at least read) about a ton of this stuff, and still, I thought it was Interesting to hear you step through a password attack in addition to hearing how modern tech and modern hacking techniques approach cracking passwords. Thank you sir.
The moment when Mike reads your password loud and shows it to 2 mil other people just on second random pause... If I could only be as lucky in some other lottery. :(
Can you believe that the bank I use has a MAXIMUM of 6 character length on the passwords used for online banking!? I have complained to them before. But to no avail. And this is not a small bank!
You should change banks then, they are just begging to have their database leaked.
Yep, You'd need to compute 2.8147498*10^14 hashes assuming that the passwords use extended ascii characters and also assuming that you know the hashing algorithm used. (Which can be achieved in a few seconds)
+moute3 Yes but the banks have other forms of authentication, including inputting specific characters of a secret answer and generating codes using your phone or hardware key.
Locut0s That doesn't make sense. That would be a reason for _not mandating_ long passwords. It can't be a reason for _forbidding_ long passwords. The only explanation for the latter is idiocy.
Locut0s I have to agree with Correctrix that if what you said is the case, then I can see why they accept weak passwords. But it does not explain why they would prevent experienced users from setting a strong password by having a maximum of 8 characters.
you forgot to link in the description
Thanks, now sorted >Sean
+Computerphile what is the disadvantage of designing your own hash for your own service? Wouldnt not knowing the hash procedure effectively eliminate the ability to crack passwords by using this method? Thanks.
+Osama Rana
also, often enough if they can get to your database, you should assume your code also isn't safe
Thank you everyone for the insightful comments.
Ps, I like the phrase "security through obscurity". That was exactly what I was thinking
'I like the phrase "security through obscurity".'
You got that this is a bad thing, right? Like, really bad? Just checking.
The video that made me change to a password manager. 4 years later and never looked back. Thanks Mike!
I like all Computerphile (and Numberphile) videos, but just wanted to say how great this particular one is. More please from Dr Mike Pound. (And prof Brailsford of course!)
"We don't save password unencrypted." Facebook left the chat 😂🤣
Hence why you change your password at least once a year.
Lol
You would be surprised how long some passwords can be if the service allows it.
Talk-Power removed
They encrypts the passwd ( I guess)
Obviously 123456 is the best password out there. And in case that doesn't work anymore. You just change it to 654321. *Genius!*
brilliant
No, 12345
@@Zooiest No, 1
BuckieTheCat Your password has to be 5-32 characters long.
Thanks what's your email? Lol
Kind of a disappointment that he never mentioned "salting" passwords before hashing them, which makes this attack completely useless if you dont know what salt was used
And even if you *do* know what salt was used, computing rainbow tables *per user* would take a substantial amount of time for a large dictionary.
you mean pepper.
salt is saved with the hash, so it just slows you down (a bit).
@@_piulin_ A salt wouldn't slow you down if you're attacking a specific user, but it would make the attack difficult to generalize since every user has a different salt and the passwords you test must have the salt at the end.
@@kalebbruwer I know, that's what I meant. If you hacked a server and got the hash file, then it's way slower when it's salted to interpret all the hashes, so you can sell them.
14:47 "ganjagoblin" XD
apparently a common password
14:45 iloveyoukate
Me too. Me too....
i smiled at linkgundam, amusingly enough.
Gaijin
lol, ganja
I am wondering how many of the viewers just saw their password in the video ^^
Totally got mine. 14:46 ILOVEYOUKATE
+Mike S I used to have that one only without "you" in it.
Everyone loves Kate, that's the problem
18:51 ashishiscool is my friend's password and his name is ashish.
+Филип Брчић genius XDDDDD
I love these videos. This guy is such a great teacher. Thank you!
Anybody else come back to this video, not to learn anything, but because this guy's voice is just so soothing?
This is actually scary, I have a LinkedIn account and I use the same password fo many other sites.
I will change all my passwords after writing this comment, and you should do too.
Just don't change all your passwords to a single new one hah.
Use a password manager. It can change them all for you automatically, and all to different passwords, and all to extremely secure passwords.
Friends. Use KeePass, it's free, open source and multiplatform. Change all your passwords. Use unique password per site. Let me know if you have any questions.
The only password I know is the one that unlocks my Keepass database.
I have KeePass on my computer and KeePass2Android on my phone. Install Dropbox to both pc and phone. Save your database or database copy there so it can be access in your pc and mobile.
Ill crack numberphile account now.
Hold my beer
Currently, for attacks on youtubers, the trend seems to be abusing a weakness with two factor auth. through social engineering. See H3h3.
The Other Other Yeah, they are using poor customer service of youtuber's mobile company. Issuing new sim cards then obtain youtuber's accounts.
"Hello my name is Tom Scott and I need a new SIM card"
"Change your hashes to something like SHA512 really quickly"
Rather recommend bcrypt or something of the like.
You need many, many more upvotes.
Or just use Secure Remote Password and not have to worry about your database getting leaked?
Cíat Ó Gáibhtheacháin I feel like I'm missing something obvious, but why do you need to store users' passwords?
rsa 4096
***** You don't store the passwords: you store something for checking if a password is valid.
it's been six years. so what hardware is used now? like to see the diffrence
a year late but usually i believe some hackers will buy 4090s with ill gotten gains
really depends on how much money the attacker has
CEO :some of our employees might want to play doom on the server.
Engineer: *installs 4 Titan Xs*
This video needs to be updated, to be shown at current levels of computer technology with the most modern CPUs & GPUs widely available to everyone.
I like these kind of practical videos better than the theoretical ones.
"If it's stored in plaintext, then all bets are off"
I have all my passwords encrypted with Caesar's cypher! Beat that!
Now that's clever!
Pah! I store my passwords using an enigma machine, weak!
@@arrowb.8438 dasoberkommandoderwehrmacht...
Arrow B. Enigma is broken. I use SIGABA
Laughs in quantum computing.
I watched this video when it came out years ago. Recently, my dad passed away and we couldn’t remember his iCloud password to access the photos on his phone and other stuff like that. But I remembered this video, and I went and found password cracking tools for iCloud and was able to use educates guesses and the tools to find the correct password. So thank you for making this video ❤️
No mention of password salting?
Are you talking about permutating your actual passwords, or salting the hashes before storing them in a database?
That's in the Tom Scott video about storing passwords.
they weren't talking about securing servers they were talking about how to crack the passwords. adding salt doesnt protect at all against the attack he used, it just makes him repeat the attack for the group of paswords with a particular salt. That would be a great followup though.
Or peppering.
koori049 "it just makes him repeat the attack for the group of paswords with a particular salt"
Well, yes, if you know the salting method you could have a guess, but the most basic of static salts can make the most awful password extremely hard to brute-force, at least as long as the salt it unknown.
"I've been running it about ...
18:15 checks wrist ... "10 seconds now"
not wearing a watch and looked completely serious
XD XD XD
XD XD XD almost as if it could potentially just be habit and he clearly realized instantly he didn't have a wrist watch on at the moment XD XD XD
@@gtc4189 XD XD XD
Plot twist: he didnt havr a wirst at all
Wurst.
I recover my instagram account back through *hackerlouis05* on instagram he’s legit and reliable 🏻 🏻 🏻
Contact @hackerlouis05 on Instagram for your hacking services he’s legit and reliable
14:47 Shoutout to ganjagoblin
Ganja means Bald in Hindi so it reads as baldgoblin
@@dishant8126 yea i bet thats what he had in mind
There is nothing like impossible to hack in this digital world. For any hack related issue Contact @cybersquad047 on Instaqram, Cybersquad047@gmail.comthanks to them I found out the truth about my spouse
@@dishant8126 I knew that... That was what I was thinking
My password one was cracked with out any software,
Me: let's make it harder
Him: is it password two
Me: how did you do that
7:54 Top row: "xiaojiji"
At first I was going to say, *wow, they've got it all in this system* , but then realized that that was probably one of the first things that got put in the database.
Really love this presentation style. More in-depth stuff please especially with exploits!
[jaw drops] you mean... my password, "cat", is weak??! Darn.
Imagine seeing your password getting cracked in this video...
Did computerphile stop asking tom scott to do videos for some reason?
he does have his own channel and probably takes up a lot of his time! check him out its pretty cool stuff.
I believe he said he'd not do too many more as he didn't know as much as some people on subjects.
Chris Gough
ty
Ikr! I love his videos on Computerphile!
I actually stopped watching Computerphile so much and started watching his channel...
Imagine being at university and using password "tictac98".
ok
I used BigPeen6969 as my password
CanIEatYourCat?
Was one my younger self used for everything. No login ever gave me an answer
most people, even supposed smart people, see the whole concept of setting a password as a nuisance rather than a necessity to prevent misuse of their account.
Why does the british lecturer always look like a Counter-Stirik Hostage.
I recover my instagram account back through *hackerlouis05* on instagram he’s legit and reliable 🏻 🏻 🏻
Contact @hackerlouis05 on Instagram for your hacking services he’s legit and reliable
@@jessicahsmith4815 thanks, Jessica Smith, Very cool.
Omega lul
Since about 2015 i've had 12 character passwords with numbers, uppercase, lowercase and symbols. So glad I did that
That awkward moment when your own password shows up on screen.
Did you used mycubana too?
Gee I wonder if MR. Putin knows him ; SIR???
12345?
MD5/SHA1/SHA256/SHA512 are Not designed for hiding passwords, never were; they're fast hashes, you need a key-stretching algorithm.
MD5-Crypt (The Poul-Henning Kamp algorithm) used by Linux and BSD were more suitable for password storage and still much harder than MD5.
Suitable modern algorithms are PBKDF2 or BCRYPT with proper number rounds and work factor.
You should be using the new winner of the Password Hashing Completion, Argon2.
Why are people referring to hashing as encryption? I've learned from studying security that's wrong. Hashing is only one-way and encryption is 2 way.
Thats right. But hashing is sometimes used in encryption, to check if the content was modified or not for example.
I think the term "Encryption" has been generalized, hashing is a one way subtype of encryption.
It's worth thinking of them as different things, but technically hashing is considered a cryptographic primitive along with asymmetric and symmetric encryption. Of course, all three have varied uses, but you can also convert these primitives to others. A feistel cipher, for instance, can turn one way hashing functions into two way symmetric encryption.
I usually say "encryption" when I'm talking to someone who maybe doesn't know what "hashing" means. It may not be accurate, but it gets the point across.
yes, but hashing is cryptography, and people tend to get cryptography and encryption confused
Scary… never thought about the hashes being stolen and put into a single file for this type of repetitive attack… defeats the thought of locking an account after a few failed attempts. Learned something again from this channel…. Thank you!
I could also never understand how passwords were brute force hacked when most services lock you out after 3 attempts. It never occurred to me that most of these databases are hacked off-line! This was a great video.
The second I see an email saying “your password was changed” ima make all my passwords unique 1000 character length
just use a password manager
@@waves_under_stars Even a simple 8 digit password generated using all possible ASCII characters (81)
All possible combinations would be 81^8 is 1,853,020,200,000,000 possible combinations.
When it's completely random with no possible way to use a Dictionary attack, and it must be guessed from the ground up.
It would take literally centuries for a standard home computer to crack. And even months for a super computer like Computer Philes "Beast" with its 400 billion guesses
@@waves_under_stars Set it above 15 digits long, completely random, and it is practically uncrackable unless they were to use some Gigantic botnet utilizing all their GPU's
@@BreadMan434 but then the problem is remembering dozen 15 digit completely random passwords. And the answer is writing them all in a txt file, encrypting it with a strong master password and remembering only the master password.
Or just use a password manager. It's essentially the same but better
@@waves_under_stars I have learned between offline and online life. That most people are lazy.
"We don't store passwords unencrypted... That is a terrible, terrible thing to do"... Facebook.
Computerphile: "Everyone's passwords are terrible"
Me: *laughs in memorised password with more than 175 characters*
Howmuchwoodcouldawoodchuckchuckifawoodchuckcouldchuckwood?Howmuchwoodcouldawoodchuckchuckifawoodchuckcouldchuckwood?Howmuchwoodcouldawoodchuckchuckifawoodchuckcouldchuckwood?
boom roasted
First ten seconds: "You have bad passwords, change them!"
Me: "N-"
Next three seconds: "Well probably not the people watching Computerphile"
Me: : )
How would a website change from using a hash algorithm to using another algorithm? Since they can't be directly unhashed. Update each password per user as soon as they log in?
probably ask the user to create a new password when they log in
Hash the existing password hashes a second time with the new algorithm, then update to use _just_ the new algorithm next time they log in.
That's a fairly common method, yeah. And if there are any concerns that the data has been compromised then most sites will force you to change your password when you next login and store that.
hash the hash
Is there any reason why some sites enforce a maximum password length? Hashes are usually fixed-size, so long passwords won't take up more space in the database.
Because shorter is easier to guess.. In 2016 nobody is worried if your passwords takes up 8 bytes of 8000 bytes really.
To increase entropy, which is the amount of possible activity of difference between different nodes (in this case possible characters in your password); if a password doesn't have too many possible guesses from the start, it will limit the amount of entropy at the end of the hashing process. Around 6:30 he talks about how it's easier to brute force lower case only passwords, that's because there isn't much entropy. That's why the websites want a varying amount of characters, like capital which effectively doubles the entropy at just the first step (without hashing, or plain text). But the thing is complexity can only go so far, because there is a limited amount of characters you can choose from on your keyboard, so the entropy increase is sort of logarithmic (starts off steep increase, but dies off quickly). But there is another way to increase entropy: length, which in fact increases entropy exponentially (another letter pushes it to a whole other level of entropy because that's one more exact letter that needs to be accounted for, which may take the machine a couple thousand or quadrillion runs around the track of checking your password). It's all about entropy and increasing it, because that makes it harder for anything to guess your password.
Chris Bernard I'm sorry you spent so much time writing that comment, but I was talking about a maximum, not a minimum length.
***** Ha misread that as well!
I don't know? aesthetics perhaps?
Now that you mention it, why not copy paste a unique binary file as a password!. Crack that!
Diggnuts Exactly.
Then there's the "Forgot your password?" feature on most sites that I'm sure can be used by identity thieves without needing a dozen RTX2080s.
@@Abanmy well people often use the same password for their email as every other site...
It's real we use almost the same password for all social media
This is the exact video which convinced me to use much better passwords that are immune to just about every attack
Yep, 3 years ago... I heard they fixed that and now password1 is back to be a legitimate password.
Thanks for the update. I can finally get rid of the capital letter in mine.
Can't image how people would feel if they see their password in the video
"change all of my passwords later tonight"
To the same thing? If so, you are still doing it wrong.
As for the parent comment, I wouldn't know if mine was, I don't know any of my passwords because, well... here, let me paste you what my password manager would have used for the next password:
P7rRD2MkwdbtrZntrNg6
*****
Be my guest! You don't NEED to break the algorithm, it is open source software.
Oh, and the reason for excluding other characters? That is my 'standard password generator', some sites don't like extra symbols and such, so it crams 100+ bits of entropy into there. If a site tells me it allows more, I just tick a few more boxes and enable such things.
*****
Here you go, if a site allows any character, you can get things like: zÛ?EíÌÏðåÆ£m8«ècâ©ßÆ
What's this "password manager" you're using ?
So, do you download LastPass every time you're borrowing the computer of someone esle ? Isn't it a bit awkward ?
"iloveyoukate" - what a romantic password.
its so romantic to have your bank account hacked because you used a weak password.
DX5Yc7Uu]&vM%;P+sI`1Fxsw)[g>Mcf=p["F^I~i.:ohuK{S?`EzSZ0e0
Maybe Kate's password was the "iloveyouivan" you see at 14:18. How sweet!
I do NOT have bad passwords. I've used a password vault for years and all of my passwords are generated by it and are around 16 characters long. My vault master password is over 20 characters long and uses digits, upper and lower case, and punctuation marks. I decided probably 10-12 years ago to get my password house in order, and it is in order.
"Fun as this is... mostly I have normal work to do" LOL
I think he's actually dive
I had used the exact same password on about 20 different accounts across the internet for years like an absolute dumbass, just recently I've finally woken up in the tech world and gone and changed every single password and made them longer than 10 characters with every type of text and character you could imagine xD... this video confirmed my paranoia.
instantly checks what my encryption service on the back end is using O.O.
Dude this is a really great explanation, I have to really thank you for this
Are rainbow tables still a useful thing?
Wondering aswell
And if you have a list of hashes without knowing the salt, the method described in this video doesn't work either.
ah I should have scrolled down same question
Shaun Husain , I don't blame you one bit. The YT commenting system is a cesspool of JavaScript which obscures a lot in the name of "well, people only want to see the latest" (and other such dimwittedness). There is no search function (of which I'm aware anyway), so to search through any more than about 10 comments is a very time consuming exercise, with all the "view all X comments" and "read more"s. So it's nearly futile to use a browser's search function to see if something has been covered already. I have no doubt left comments that were redundant, because finding one that I can simply plus-one/thumbs up is, unfortunately, exceedingly tedious.
I think one of the points here is that MD5 hashing is so fast on modern CPU/GPUs, you don't even need rainbow tables for a effective attack.
If we are talking about harder/slower hashing algorithms, like those recommended; rainbow tables would still be an effective attack against non-salted passwords.
So who's passwords are being shown/figured out using Hashcat?
If I've learned anything from this video, it's that you shouldn't store your passwords in plain text-- hash them using MD5.
other than him specifically stating NOT to use MD5 lol
As a note from the future: please do not use SHA-512 for your passwords either. Choose a proper algorithm designed for password hashing (like pbkdf2 or others) that do proper iterations and have salting built-in. OWASP does list proper algorithms for this case.
Best is still to not store passwords at all. Use auth providers or integrate passkeys.