The Heartbleed SSL vulnerability had a distinct impact on US web users' security perceptions, according to a study from the Pew Research Internet Project.
Pew studied the reactions of 1,500 US internet users in the weeks following the disclosures about the bug, which could have affected as many as half a million websites. It found that 39 percent of web users were compelled to shut down accounts to avoid risk of exposure.
Pew Internet said: "The flaw basically allowed people to 'break the lock' on sophisticated encryption software, get into the memory of security systems and gather up whatever personal information was there, including usernames, passwords, and the actual content of accounts such as credit card data or other sensitive personal information."
Thirty-nine percent of people spoken to in the survey admitted that they had closed accounts or changed passwords as a result, six percent were concerned that they might have lost personal information, and 29 percent believed that their data was put at risk. Of those who had heard of Heartbleed before starting the survey, 45 admitted that they felt vulnerable.
Pew Internet found that it was "upscale", well-educated and well-paid, web users who felt closest to risk, and said that university graduates were more concerned than those with a high school diploma.
It added: "Similarly, internet users in higher-income households were more likely than those in lower-income households to fear that Heartbleed put their information at risk. Thirty-four percent of the internet users living in households earning $75,000 or more said the bug put their information at risk, compared with 25 percent of the internet users living in households earning less than $30,000."
Overall seven out of 10 Americans believe that their web accounts are secure to some degree. Thirteen percent feel that their information is not secure at all.
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