A Cloudflare bug is responsible for leaking sensitive data from several different websites.

Cloudflare is a web company that hosts content for over 2 million websites. A recent bug has been discovered that can allow users to access private data from some of those websites. The data leak can includes messages, passwords and more.

The data leak problem stems from browsers accessing the websites. The issue made it so that each time the website was reached, there was a chance that it would leak data to the browser. This means that random users could have other users’ passwords and private data. The tactic could have been used maliciously to steal private information.

CloudFlare is aware of the bug and has fixed it. It notes that there is no evidence that it was used to steal information. The company has been working with others to determine how many websites were affected by the leak. This search has turned up 161 different domains that have been affected by the bug, reports Forbes.

“The memory being leaked was from a process based on NGINX that does HTTP handling,” John Graham-Cumming, Cloudflare’s CFO, said in a blog post. “It has a separate heap from processes doing SSL, image re-compression, and caching, which meant that we were quickly able to determine that SSL private keys belonging to our customers could not have been leaked.”

Since CloudFlare serves so many different websites, it may be hard for users to track down which ones were affected by the bug. As a result, it may be a good idea for people to change all of their passwords.