
Breaking homegrown crypto - tdurden
https://kivikakk.ee/cryptography/2016/02/20/breaking-homegrown-crypto.html
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tptacek
Great writeup! If you want to work on a similar problem that targets the
fundamental insecurity of ECB mode to the same end, we have an exercise that
walks you through it here:

[http://cryptopals.com/sets/2/](http://cryptopals.com/sets/2/)

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Tomte
The author remarked in his Snapchat post from 2013 that the Matasano Crypto
Challenges have been helpful. So I guess he made it past set 2. :-)

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abbasaamer
This is probably one of the most concise and easy to follow articles I've read
on this subject. Thanks for the great post!

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mchahn
I wonder how long he worked to craft the excellent analysis and crack
software? I know an attacker would be motivated to do this but he spent the
effort just for a blog post? I'm very happy he did.

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CiPHPerCoder
This is an excellent write-up.

In case anyone is concerned, this bears repeating: This attack broke
CodeIgniter 2's poorly designed Encrypt class, but CodeIgniter 3's Encryption
class offers authenticated encryption.

If you're still using CodeIgniter 2, upgrade.

If you're using CodeIgniter 3, make sure you're not using Encrypt.

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woah
Sounds like it might be safest not to use CodeIgniter.

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CiPHPerCoder
What tool to use is a decision that developers and companies have to make for
themselves. I can't make it for them, so I usually don't try.

Exception: Don't use mcrypt. It's abandonware.

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77pt77
Excellent article.

Reads almost like a walk through.

Side note: Why is a .ee (Estonia) domain site hosted in Japan (Tokyo)?

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ross-life
I was thinking it was part of the site's name, as in "kivi-kak-kee" or they
just dislike .com/.co's.

Similar to many start-ups and tech projects being hosted <everywhere> on .io
(Indian Ocean) domains.

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emerongi
"Kivikakk" is a bird in Estonian.

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77pt77
So it is indeed related to Estonia.

Regarding the geographic location, it's probably a Choopa/vultr machine.

Seems like a digitalocean clone though with more geographical locations and
they support arbitrary OS images.

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pklausler
Well-written, worth the read.

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atirip
[https://news.ycombinator.com/from?site=kivikakk.ee](https://news.ycombinator.com/from?site=kivikakk.ee)

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dang
HN doesn't treat posts as dupes when a story hasn't had significant attention
yet. See
[https://news.ycombinator.com/newsfaq.html](https://news.ycombinator.com/newsfaq.html).

This is because we want good stories to have multiple chances at making the
front page. The current story is a great example. In fact, we invited tdurden
to repost it, as we sometimes do when we notice an article that we think the
community might find interesting, but which fell through the cracks.

We're working on a better duplicate handling system that will reduce the
number of reposts in the story stream, but getting it right is surprisingly
subtle, and we'd rather take longer than get it wrong.

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pklausler
And my thanks for doing so with this story, which I'm glad to have had a
second chance at discovering.

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whatnotests
Reading this on an iPhone is a terrible way to spend my Saturday afternoon
with a jumpy page scrolling all over the place.

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jgalt212
here's a good rule of thumb:

If it's longer than a tweet, don't read it on your phone.

