Even patching SSL is no simple task, Bailey said. Sites may be running multiple versions of SSL, so administrators have to take care to be thorough and keep testing for the vulnerability, he said. Small businesses, in particular, may not get their sites fixed for some time, Bailey said.
On Wednesday, Yahoo acknowledged its platform was vulnerable to Heartbleed and said it started working on a fix as soon as it knew about the problem.
"Our team has successfully made the appropriate corrections across the main Yahoo properties (Yahoo Homepage, Yahoo Search, Yahoo Mail, Yahoo Finance, Yahoo Sports, Yahoo Food, Yahoo Tech, Flickr and Tumblr) and we are working to implement the fix across the rest of our sites right now," a company representative said via email.
Google has also been working on the problem. "We've assessed this vulnerability and applied patches to key Google services such as Search, Gmail, YouTube, Wallet, Play, Apps, and App Engine. Google Chrome and Chrome OS are not affected. We are still working to patch some other Google services," the company said in a blog post. Among those were Cloud SQL and Google Search Appliance. For customers of Google Compute Engine, the company laid out steps that users themselves need to take.
Facebook said it had added protections to its OpenSSL implementation before the problem was publicly disclosed and was still watching the situation. "We haven't detected any signs of suspicious account activity that would suggest a specific action, but we encourage people to take this opportunity to follow good practices and set up a unique password for your Facebook account that you don't use on other sites," Facebook said in a statement.
"We are following reports of an OpenSSL library issue. If we determine there is an impact to our devices and services, we'll take necessary steps to protect our customers," a Microsoft representative said.
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