Yes, we know that you know that Twitter was down for a little while earlier today, we just wanted you to know what caused it. Too bad we can’t definitively tell you!

Twitter continues to blame the outage on a cascading bug, but there’s a group claiming otherwise.

According to the hacktivist group UGNazi, they took Twitter down today – not some “cascading bug:”

Why would they do this? According to CNET:

Hacker Hannah Sweet, known as “Cosmo” and @CosmoTheGod on Twitter, said UGNazi took Twitter down for 40 minutes worldwide with a “distributed denial of service” attack and the hackers are continuing to do so.

Sweet said that the group attacked Twitter because of the site’s support of Cyber Intelligence Sharing and Protection Act (CISPA), a bill that allows the federal government and private businesses to share information about possible cyber threats.

And they’ve posted a target list of other places they plan to take down, including Google (among others).

BUT, Twitter just posted the following update about the outage, denying any hack took place:

This wasn’t due to a hack or our new office or Euro 2012 or GIF avatars, as some have speculated today. A “cascading bug” is a bug with an effect that isn’t confined to a particular software element, but rather its effect “cascades” into other elements as well. One of the characteristics of such a bug is that it can have a significant impact on all users, worldwide, which was the case today. As soon as we discovered it, we took corrective actions, which included rolling back to a previous stable version of Twitter.

Sounds plausible. But what do you think?

(Question marks image from Shutterstock)