An example of the "mouseover" code exploit being used on Twitter: this example is harmless but many others are not. Source: Sophos.com
From The Guardian:
Bug in new-look site exploited to redirect viewers on Twitter.com if they just hover over a link - but users of third-party software are safe (updated)
Update: the flaw has been fixed, and Twitter now says it is safe to use twitter.com again.
Sarah Brown is among thousands of Twitter users who have been hit by malicious use of a security flaw in the redesigned Twitter site.
The wife of the former prime minister Gordon Brown, who has more than a million followers on Twitter, unknowingly sent a link which contained malicious code that would redirect anyone who moved their mouse over it - but didn't click it - to a Japanese hard-core pornography site.
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