Sophos warns Twitter users as ‘Onmouseover’ security flaw widely exploited
September 2010 by Sophos
IT security and data protection firm Sophos is warning computer users to be cautious in the wake of a widespread security flaw affecting popular micro-blogging site Twitter. The Twitter website is being widely exploited by users who have stumbled across the flaw which allows messages to pop-up and third-party websites to open in your browser just by moving your mouse over a link.
Thousands of Twitter accounts have posted messages exploiting the flaw, with victims including Sarah Brown, wife of the former British Prime Minister whose Twitter page appears to have been messed with in an attempt to redirect visitors to a hardcore porn site hosted in Japan.
“It seems many users are currently using the flaw for fun and games, but there is obviously the potential for cybercriminals to redirect users to third-party websites containing malicious code, or for spam advertising pop-ups to be displayed,” said Graham Cluley, senior technology consultant, Sophos. “Some users are also exploiting the loophole to create tweets that contain blocks of colour (known as rainbow tweets). Because these messages can hide their true content, it might prove hard for some users to resist clicking on them. Hopefully Twitter will shut down this loophole as soon as possible – disallowing users to post the onMouseOver JavaScript code.”