Heartbleed is a bug that made services using OpenSSL encryption vulnerable to attack, including websites, instant messaging software and email accounts. It's worth noting that not all website are affected by the heartbleed bug.
According to data analysis website Datanyze, 17.3 percent of the top 1 million websites ranked by Alexa.com may have been exposed to heartbleed. Internet data company Netcraft reports that a recent survey found 17.5 percent of website that use secure socket layer (SSL) encryption. For many, it's unclear which websites are still at risk, so it's worth taking extra precaution.
"If the website is still vulnerable, changing the password will not accomplish anything. The hacker could potentially view your newly created password, too," Dodi Glenn, director of security intelligence at ThreatTrack Security, told CBS News via email.
Glenn says there are websites to check whether or not a website has been patched, and suggested filippo.io/heartbleed or ssllabs.com/ssltest. Password management software maker LastPass also has a service that checks if a website is vulnerable. LastPass recommends users of websites like Yahoo, GitHub and Fitbit update their passwords right away. But if you have a Netflix, Airbnb or Quora account, wait to update.
Trend Micro vice president of security research Rik Ferguson told CBS News via email that if you update too early, not only are you putting your new password at risk, you could be exposing additional data that is requested during the password reset process. Ferguson suggests avoiding services that are not yet patched, until a security fix is released.
"If it is not possible to avoid logging in to a service then continue as normal, changing your password will not bring you any extra security until the server is patched," Ferguson said.
But if you have the same password for several different websites or services, then changing your password right away. Ferguson adds, "any exposure of a shared password may have wider consequences."
Ferguson says you should change your password once you've been notified or discover that a server has had a security update. He suggested avoiding these big mistakes when creating a new password: using words from the dictionary, names, dates of birth, ages, telephone numbers, pet's names, football teams or anything related to you.
Don't use the same password for different services and never share your password. Even words using numbers in place of letters is not secure enough. Ferguson says a word like "P455w0rd" can be cracked within minutes.
Ferguson shared an example of five steps for creating a more secure password.
1. Think of a phrase you can easily remember, for example:
"Motley Crue and Adam and the Ants were the soundtrack of my youth."
2. Take the initial letter of each of those words:
3. This will be the basis of the password, but we now need to make sure we use upper and lower case characters, numbers and "special characters" like !$&+ for example, let's change cases first:
4. Now change some of those letters for numbers, maybe the letter O to a zero
5. Now add the special characters, I'll change the "and" into + and &
Ferguson suggests creating variations of the password for different websites, like adding the first and last letter of a website name at the beginning or end of a password. He adds that users also need to be aware of phishing scams that attempt to lure people to fake websites.
Mandiant security security expert William Ballenthin told CBS News in an interview that heartbleed compromises past and future communications with a server, like banking or email transactions. He adds that this bug has been "in the wild" for about two years, and was only recently discovered. At this point not much can be done about the past.
But Ballenthin says major websites like Google, Amazon and Yahoo have identified the issues and released a fix. According to tech website Mashable, several major banks are not affected because they do not use OpenSSL encryption software. The website released a list of major sites that were infected by the heartbleed bug and have since been updated, including Facebook, Pinterest, Tumblr, Gmail, Yahoo, Amazon and Dropbox.