How TweetDeck's Massive Outage Unfolded

A cyber worm breached Twitter's companion app, Tweetdeck, which hijacked user accounts and retweeted jumbled computer code.

How TweetDeck's Massive Outage Unfolded
Flickr / Dan Coulter

It caused an internet uproar Wednesday. Twitter took down its popular Tweetdeck app after a flaw left it vulnerable and user accounts were subsequently hijacked.

During the breach, some Twitter users who opened the popular multi-window organizer involuntarily retweeted this line of code from user account @derGeruhn. And, if you look closely, you'll notice the computer gibberish was retweeted about 85,000 times.

And The Guardian said the first 38,000 came in the span of 2 minutes.

According to The Verge, other users reported seeing pop-up windows with alarming notes such as: "Yo!" and "Please close now TweetDeck [sic], it is not safe."

ABC also said the bug affected some pretty big-name users including news outlets like @NYTimes, @CBCNews and @BBCBreaking.

Mashable reports Twitter took Tweetdeck offline due to what's called XSS or "cross-site scripting."

Web security company Acunetix says it's "one of the most common application-layer web attacks" which goes after the user's browser instead of the server.

Tweetdeck did apologize for the mishap and said – after a few hangups – they fixed the security breach. 

It appears the site is now up and running again. Twitter said you just need to sign off Tweetdeck then jump back on to apply the patch.

So, who was the man behind the madness?

According to CNN, the cyber ruckus spawned from an Austrian teenager called Florian. The computer science student said he was "just experimenting" when he found out using the heart symbol on Tweetdeck allowed him to toy with programs using tweets.

Florian told CNN, "It's horror that TweetDeck made that mistake. ... It's horror that [hackers] are using this issue. I don't know. I'm sad in a way."

Florian reportedly even told Twitter he discovered the flaw, but also told the Twitterverse as well which is when the hack started making its rounds.