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Evernote hacked

blog.evernote.com

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61–70 of 220 posts

Re: Evernote hacked

#61

Post by floody-berry »

UnoriginalGuy wrote: post #29
kmfrk wrote: post #19

Earlier quoted context omitted.

"One-way encryption" is a peculiar choice of phrase.

No, it is an accurate choice of phase. The passwords are "hashed" which is literally one-way encryption, since the encryption is lossy - the information to reverse it literally doesn't exist in the output. The only way to "break" correctly working hashes is to encrypt tons of passwords (+salt) and see if the lossy output is identical to the output you got from the previously hashed password. Which is a very time cons…

"hashed and salted" is not necessarily time consuming, it really matters what process they used. Their post gives no confidence that the passwords cannot be trivially cracked.

Re: Evernote hacked

#62

Post by sdevlin »

apawloski wrote: post #27
kmfrk wrote: post #19

Earlier quoted context omitted.

"One-way encryption" is a peculiar choice of phrase.

Meh, it's a PR person who probably had it explained 10 minutes before. They explicitly state that they are hashed and salted, so I'm not super concerned.

Depending on how they're hashed, that may or may not be an effective countermeasure.

Re: Evernote hacked

#63

Post by apawloski »

UnoriginalGuy wrote: post #44
apawloski wrote: post #33

Earlier quoted context omitted.

People are going to argue with you semantically, but you'll all generally be in agreement (except 3DES is a block cipher, not a hash function).

3DES is a black cipher but block ciphers can be used for hashing. 3DES in particular was used on UNIX/Linux based systems quite extensively. http://www.freebsd.org/doc/handbook/crypt.html See this: http://en.wikipedia.org/wiki/One-way_compression_function#Co...

Yeah, in retrospect I should have realized that (especially with bcrypt, also made from a block cipher, being the current standard for password storage). I didn't know DES was actually used for hashing though (perhaps unfortunately revealing my younger age and naiveté :)

Re: Evernote hacked

#64

Post by [deleted] »

kmfrk wrote: post #19
UnoriginalGuy wrote: post #11

The following blog post is also being sent to all Evernote users as an email communication. Evernote’s Operations & Security team has discovered and blocked suspicious activity on the Evernote network that appears to have been a coordinated attempt to access secure areas of the Evernote Service. As a precaution to protect your data, we have decided to implement a password reset. Please read below for details and inst…

"One-way encryption" is a peculiar choice of phrase.

[deleted]

Re: Evernote hacked

#65

Post by UnoriginalGuy »

NoPiece wrote: post #60
jgrahamc wrote: post #36

Earlier quoted context omitted.

Even though this information was accessed, the passwords stored by Evernote are protected by one-way encryption. (In technical terms, they are hashed and salted.( http://en.wikipedia.org/wiki/Salt_(cryptography) )) That's great. But to really reassure people they would do best to reveal the algorithm. After all, DES-based password hashes are both 'hashed and salted' but are easily broken with JtR.

Curious, if the attacker knows what the encryption algorithm is, does it help them at all in breaking it? I.e., does it potentially delay breaking it by not revealing it?

In theory, yes, in practice it is fairly obvious how something is hashed just by eye. Different hash algorithms produce different output (lengths, starting character, and spread).

So with some experience you can often tell (or guess and test) what something is hashed with.

Re: Evernote hacked

#67

Post by aw3c2 »

tomjen3 wrote: post #37
UnoriginalGuy wrote: post #11

The following blog post is also being sent to all Evernote users as an email communication. Evernote’s Operations & Security team has discovered and blocked suspicious activity on the Evernote network that appears to have been a coordinated attempt to access secure areas of the Evernote Service. As a precaution to protect your data, we have decided to implement a password reset. Please read below for details and inst…

I haven't received such an email, wonder why. Anyway Evernotes android client wasn't very good and it was far too slow to start. And now the have been hacked. Anybody know a good alternative?

Seconding that request but for a local app. I would not ever want my notes to be available to strangers under any circumstances.

Re: Evernote hacked

#69

Post by raverbashing »

NoPiece wrote: post #60
jgrahamc wrote: post #36

Earlier quoted context omitted.

Even though this information was accessed, the passwords stored by Evernote are protected by one-way encryption. (In technical terms, they are hashed and salted.( http://en.wikipedia.org/wiki/Salt_(cryptography) )) That's great. But to really reassure people they would do best to reveal the algorithm. After all, DES-based password hashes are both 'hashed and salted' but are easily broken with JtR.

Curious, if the attacker knows what the encryption algorithm is, does it help them at all in breaking it? I.e., does it potentially delay breaking it by not revealing it?

No, it's usually known by the format, or even stored together with the password

Example: crypt stored the password in the format: $id$salt$encrypted

Re: Evernote hacked

#70

Post by sdevlin »

[deleted] wrote: post #57
jgrahamc wrote: post #36

Earlier quoted context omitted.

Even though this information was accessed, the passwords stored by Evernote are protected by one-way encryption. (In technical terms, they are hashed and salted.( http://en.wikipedia.org/wiki/Salt_(cryptography) )) That's great. But to really reassure people they would do best to reveal the algorithm. After all, DES-based password hashes are both 'hashed and salted' but are easily broken with JtR.

[deleted]

This is not accurate. If it were, what would be the point of hashing at all?

Password hashes like scrypt, bcrypt, and PBKDF2 are specifically designed to be slow, such that breaking them takes not weeks but many years.

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