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Check if your email is amongst those compromised in Gawker break-in

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Re: Check if your email is amongst those compromised in Gawker break-in

#21

Post by izak30 »

jdludlow wrote: post #5
jedsmith wrote: post #4

What is the point of including the domain tied to the address? It just decreases the anonymity of what you've hashed, and actually does a disservice. There are corporate domains in there and the namespace of what to search for becomes a lot smaller. In addition, my domain is my name. I saw many others in the file that this was the case for. It's not a big leap to compute my e-mail from 'jedsmith.org', and I'm sure it…

I like it. OS X users, if you are paranoid about using online tools for the SHA-256 hashing, you can do this from the command line with sha256deep. Via Homebrew it'd go like this (replace the 1st step with whatever package manager you like): $ brew install md5deep $ echo -n my@email | sha256deep d869524229c1e2f6139194fee1aac14f873b008dd0279458cbdfb6b3fbade1d2

Also

python

>import hashlib

>hashlib.sha256("you@yourdomain.com").hexdigest()

Re: Check if your email is amongst those compromised in Gawker break-in

#22

Post by ABrandt »

aneesh wrote: post #20
ABrandt wrote: post #16

For some reason every md5 from this spreadsheet I try to decrypt, I get nothing. I'm using online tools like md5decrypter.com to do this. Am I missing something?

md5 is a hash function, and hash functions are designed to have two properties: 1) they are hiding . You (theoretically) can't reverse the function by any method other than brute-force. 2) they are *binding. You (theoretically) can't find any other input that hashes to the same output by any method other than brute-force. Any tool that "decrypts" md5 hashes most likely does so by generating what is called a rainbow t…

Okay thank you for the explanation. Let me try and apply my rudimentary knowledge here...

So a hash function is used to encrypt data by translating it with a certain rule set--I've learned about a simple key%b type function before. But with md5 this hashing function isn't the same each time a new code is created? How is the system able to decode it then? _Something_ out there has to know how to translate that back into a readable string right?

And collision is when different strings end up with the same encrypted code (except if you use a hash chain structure). So how is this used in an attack?

Sorry for all the questions. I know I could probably google this but I always learn better through instruction. Thanks!

Re: Check if your email is amongst those compromised in Gawker break-in

#23

Post by sirn »

jdludlow wrote: post #5
jedsmith wrote: post #4

What is the point of including the domain tied to the address? It just decreases the anonymity of what you've hashed, and actually does a disservice. There are corporate domains in there and the namespace of what to search for becomes a lot smaller. In addition, my domain is my name. I saw many others in the file that this was the case for. It's not a big leap to compute my e-mail from 'jedsmith.org', and I'm sure it…

I like it. OS X users, if you are paranoid about using online tools for the SHA-256 hashing, you can do this from the command line with sha256deep. Via Homebrew it'd go like this (replace the 1st step with whatever package manager you like): $ brew install md5deep $ echo -n my@email | sha256deep d869524229c1e2f6139194fee1aac14f873b008dd0279458cbdfb6b3fbade1d2

…or without installing anything:

    $ echo -n 'my@email' |openssl dgst -sha256
    d869524229c1e2f6139194fee1aac14f873b008dd0279458cbdfb6b3fbade1d2

Re: Check if your email is amongst those compromised in Gawker break-in

#24

Post by edanm »

ABrandt wrote: post #22
aneesh wrote: post #20

Earlier quoted context omitted.

md5 is a hash function, and hash functions are designed to have two properties: 1) they are hiding . You (theoretically) can't reverse the function by any method other than brute-force. 2) they are *binding. You (theoretically) can't find any other input that hashes to the same output by any method other than brute-force. Any tool that "decrypts" md5 hashes most likely does so by generating what is called a rainbow t…

Okay thank you for the explanation. Let me try and apply my rudimentary knowledge here... So a hash function is used to encrypt data by translating it with a certain rule set--I've learned about a simple key%b type function before. But with md5 this hashing function isn't the same each time a new code is created? How is the system able to decode it then? _Something_ out there has to know how to translate that back in…

"_Something_ out there has to know how to translate that back into a readable string right?"

Wrong. That's exactly your misunderstanding - MD5 is not an encryption function, but a hashing function.

The way it works is, given some string, it will output a new, random-looking string. It's impossible to go backwards, i.e. given the output of running MD5, you can't tell the input.

In a nutshell, The way password authentication works is this: when you sign up to a site, a hash of your password is saved. At this point no one, not even the site itself, can tell what your password was.

When you want to log in, you send the password over to the site, they hash it again, and compare the output with the saved hash. If you put in the same password, the hash will come out the same. And it's very, very hard to find a different string which isn't your password which will get you the same hash output.

Re: Check if your email is amongst those compromised in Gawker break-in

#26

Post by il »

If your email is in that list, expect it to get spammed heavily in the coming days.

While it's nice of random social whatever startup hint.io to warn people that their password is compromised, linking to their landing page multiple times in the email makes me think they have ulterior motives.

Re: Check if your email is amongst those compromised in Gawker break-in

#27

Post by bigiain »

edanm wrote: post #24
ABrandt wrote: post #22

Earlier quoted context omitted.

Okay thank you for the explanation. Let me try and apply my rudimentary knowledge here... So a hash function is used to encrypt data by translating it with a certain rule set--I've learned about a simple key%b type function before. But with md5 this hashing function isn't the same each time a new code is created? How is the system able to decode it then? _Something_ out there has to know how to translate that back in…

"_Something_ out there has to know how to translate that back into a readable string right?" Wrong. That's exactly your misunderstanding - MD5 is not an encryption function, but a hashing function. The way it works is, given some string, it will output a new, random-looking string. It's impossible to go backwards, i.e. given the output of running MD5, you can't tell the input. In a nutshell, The way password authenti…

"The way password authentication works is this: when you sign up to a site, a hash of your password is saved."

That's an assumption that's been proven wrong _way_ too many times...

Re: Check if your email is amongst those compromised in Gawker break-in

#28

Post by abraham »

jedsmith wrote: post #4

What is the point of including the domain tied to the address? It just decreases the anonymity of what you've hashed, and actually does a disservice. There are corporate domains in there and the namespace of what to search for becomes a lot smaller. In addition, my domain is my name. I saw many others in the file that this was the case for. It's not a big leap to compute my e-mail from 'jedsmith.org', and I'm sure it…

Why even bother hashing the email addresses when the entire dump can be downloaded with bit torrent.

Re: Check if your email is amongst those compromised in Gawker break-in

#29

Post by jrmg »

sirn wrote: post #23
jdludlow wrote: post #5

Earlier quoted context omitted.

I like it. OS X users, if you are paranoid about using online tools for the SHA-256 hashing, you can do this from the command line with sha256deep. Via Homebrew it'd go like this (replace the 1st step with whatever package manager you like): $ brew install md5deep $ echo -n my@email | sha256deep d869524229c1e2f6139194fee1aac14f873b008dd0279458cbdfb6b3fbade1d2

…or without installing anything: $ echo -n 'my@email' |openssl dgst -sha256 d869524229c1e2f6139194fee1aac14f873b008dd0279458cbdfb6b3fbade1d2

Or, with the cryptically named 'md5'...

    echo -n 'my@email' | md5

Re: Check if your email is amongst those compromised in Gawker break-in

#30

Post by estel »

bradgessler wrote: post #14
jrockway wrote: post #9

Fuck. What the fuck did I even need a Gawker account for? (Thanks for making this. I was going to download the torrent, but assumed that I did not ever visit their site, much less make an account. Wrong!)

You needed it if you commented on a post.

Unless you posted with Facebook or Twitter auth
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