On Monday, November 25, Facebook and Twitter said private data of “hundreds of their users” was compromised through malicious third-party Android apps. The social media companies were tipped off by a team of security researchers who discovered that a software developer kit called One Audience allowed developers to access personal information they weren’t supposed to.
In addition to data such as email addresses and usernames, the vulnerability also exposed users’ recent tweets if they logged into those bad apps with their Twitter account. While the report doesn’t share specifics on the Android apps, CNBC says popular photo-editing apps like Giant Square and Photofy may be among them — the former of which has already been taken down from the Google Play Store.
The issue, as one would expect, didn’t originate due to oversights in Twitter and Facebook’s frameworks. Instead, the companies suggest it was caused by the lack of sufficient isolation between software developer kits within a single app on Android.
The majority of apps today employ multiple external tools for enabling different services like advertising and analytics. Since, according to Twitter, there wasn’t a stringent set of security walls to separate each of those, the OneAudience SDK was able to tap into the rest.
“While we have no evidence to suggest that this was used to take control of a Twitter account, it is possible that a person could do so,” added Twitter in a blog post.
“Security researchers recently notified us about two bad actors, One Audience and Mobiburn, who were paying developers to use malicious software developer kits (SDKs) in a number of apps available in popular app stores. After investigating, we removed the apps from our platform for violating our platform policies and issued cease and desist letters against One Audience and Mobiburn,” said a Facebook spokesperson.
Even though Twitter has pinned the breach on Android’s shortcomings, it’s still unclear how the OneAudience SDK stole users’ private data. Authentication APIs by Facebook and Twitter are not supposed to directly share information with third-party partners in the first place.
Twitter and Facebook have notified Google and Apple of the vulnerability but haven’t commented on whether they plan to reprogram their apps to prevent a breach like this from happening again in the future.
Earlier this month, a Facebook bug gave its app background access to iOS users’ cameras and a week before that, it was found that private data of thousands of Facebook group members had been compromised.