Twitter Tells it’s Users that Firefox Cached Private Data For Up to 7 Days


On Thursday, Twitter told the users that the way the Firefox web browser stores cached data that reveal their personal information.

The social media giant recently found out that Firefox’s cache saved some private Twitter-related data, including direct messages sent or received, and the data archive downloaded. However, on accessible computers, this would be problematic only.

“We recently learned that the way Mozilla Firefox stores cached data may have resulted in non-public information being inadvertently stored in the browser’s cache,” Twitter said.


“This means that if you accessed Twitter from a shared or public computer via Mozilla Firefox and took actions like downloading your Twitter data archive or sending or receiving media via Direct Message, this information may have been stored in the browser’s cache even after you logged out of Twitter.”


The company added in a message posted on Twitter, “There isn’t a standard for how browsers cache downloaded data. We noticed that the way Firefox stores cached Twitter data is different (but not wrong) than other browsers and could put your non-public info at risk.”

For seven days only, Firefox stored cached data, meaning that Twitter data were only exposed for a limited period. Users can also clear the cache manually, as suggested by Twitter for users who use a can or public computer to access Twitter.

Twitter has updated its content to ensure that Firefox no longer holds potentially confidential user information. It does not appear that Safari and Chrome were affected.

During the past few years, Twitter revealed a range of security problems and privacy concerns such as the use of advertisement account security data, the Android app with a secure tweet, an API vulnerability that matches username numbers to telephone numbers, the Android app which provides hackers with access to sensitive data and hijacks accounts, and third party direct messages.

Mark Funk
Mark Funk is an experienced information security specialist who works with enterprises to mature and improve their enterprise security programs. Previously, he worked as a security news reporter.