UserVoice Security Incident Notification

Post by runesoerensen » Tue, May 10, 2016, 5:10 AM UTC

tempestn wrote: post #9

runesoerensen wrote: post #8

Earlier quoted context omitted.

I wouldn't call resetting passwords an "abundance of caution" in this case. It's very likely that the attackers are able to retrieve passwords when they have the SHA1 hash and the salt (not exactly by decrypting though). Here's a good blog post how and why this is problematic: https://www.troyhunt.com/our-password-hashing-has-no-clothes...

Do they say somewhere that they're only using sha1 though? That's sort of what I meant: if bcrypt or scrypt is used, with an appropriate work factor, the risk should be very minimal. The fact that they're assuming it's not suggests they are using weaker encryption.

Post by runesoerensen » Tue, May 10, 2016, 7:37 AM UTC

tempestn wrote: post #12

runesoerensen wrote: post #11

Earlier quoted context omitted.

Yes they said that in the first paragraph of the incident report you posted a link to ;) Unfortunately, the passwords were hashed with the SHA1 hashing algorithm, which by today’s standards is considered weak Also, hashing != encryption

Ahh thanks. I read the email they sent out, which had very similar content, but omitted that bit. Just skimmed the post itself, but obviously missed that key info. Interesting that they don't include strengthening their encryption (ok, hashing) in the list of steps they plan to take, but presumably they will.