Facebook: Millions of Instagram users' passwords stored in 'readable format'

Facebook revealed last month that tens of thousands of Instagram users' passwords were being stored unencrypted in a "readable format" within the company's internal data storage systems, but updated their blog Thursday to say that the issue potentially impacted millions of Instagram users' passwords instead.

"Since this post was published, we discovered additional logs of Instagram passwords being stored in a readable format," Facebook said in their blog post. "We now estimate that this issue impacted millions of Instagram users."

Facebook said it would be notifying these users "as we did the others."

The social media company also said that it estimates hundreds of millions of Facebook Lite users and tens of millions of other Facebook users were affected. It said it will also notify those users.

Facebook Lite is a version of Facebook predominantly used by people in regions with lower connectivity, according to the company.

The company's login systems are designed to mask passwords using techniques that make them unreadable, Facebook said. But Facebook said their investigation has determined that these stored passwords were "not internally abused or improperly accessed."

In the initial March post, the company said that the passwords were not visible to anyone outside of Facebook.

The initial post also said the company has "fixed these issues," but it's unclear if the solution included the millions of Instagram users' readable passwords that were revealed Thursday to have been stored unencrypted.

This story was reported from Los Angeles.