California-based social networking giant Facebook has reported a security breach affecting 50 Mn accounts. The Facebook security breach happened on September 25, when Facebook’s engineering team discovered a security issue.
The company has not revealed any specific details with respect to countries whose users have been affected by this security breach.
Apparently, the attackers exploited a vulnerability in Facebook’s code that impacted “View As”, a feature that lets people see what their own profile looks like to someone else. This attack exploited the complex interaction of multiple issues in the code.
“This allowed them to steal Facebook access tokens which they could then use to take over people’s accounts. Access tokens are the equivalent of digital keys that keep people logged in to Facebook so they don’t need to re-enter their password every time they use the app,” said Facebook in a media statement.
What Happened Exactly?
Citing some technical details around the Facebook security breach, the company explained that the vulnerability was the result of the interaction of three distinct bugs:
First: ‘View As’ should be a view-only interface. However, for one type of composer (the box that lets you post content to Facebook) — specifically the version that enables people to wish their friends happy birthday — View As incorrectly provided the opportunity to post a video.
Related Article: Facebook Recent Hack Affected 30 Mn Accounts, Not 50 Mn: Guy Rosen
Second: A new version of Facebook video uploader (the interface that would be presented as a result of the first bug), introduced in July 2017, incorrectly generated an access token that had the permissions of the Facebook mobile app.
Third: When the video uploader appeared as part of View As, it generated the access token not for you as the viewer, but for the user that you were looking up.
It was the combination of these three bugs that became a vulnerability: when using the View As feature to view a user’s own profile as a friend, the code did not remove the composer that lets people wish the user happy birthday; the video uploader would generate an access token when it shouldn’t have; and when the access token was generated, it was not for the user but the person being looked up.
That access token was then available in the HTML of the page, which the attackers were able to extract and exploit to log in as another user. The attackers were then able to pivot from that access token to other accounts, performing the same actions and obtaining further access tokens.
Actions Taken By Facebook So Far
Facebook has taken below-mentioned actions so far to control the situation:
- fixed the vulnerability and informed law enforcement
- reset the access tokens of the affected 50 Mn accounts as well as another 40 Mn vulnerable accounts
- temporarily turning off the “View As” feature while we conduct a thorough security review.
“As a result, around 90 Mn people will now have to log back in to Facebook, or any of their apps that use Facebook Login. After they have logged back in, people will get a notification at the top of their News Feed explaining what happened,” said the company.
The investigation is currently at an early stage and the company is yet to determine whether these accounts were misused or any information accessed. Facebook also apologised for the security breach to its audience.
“People’s privacy and security is incredibly important, and we’re sorry this happened. It’s why we’ve taken immediate action to secure these accounts and let users know what happened.”
Earlier, in April this year, Facebook Chief Mark Zuckerberg made the revelation that 5.62 Lakh people in India were ‘potentially affected’ by the global data leak crisis – the Facebook-Cambridge Analytica issue wherein the data of 87 Mn Facebook users was leaked.
The company had to face a lot of heat from the governments globally and is still facing questions from many including the Indian government. As a result, Facebook’s social messaging app WhatsApp is also facing troubles in getting its digital payment plans approved by the Indian authorities.
With 20 Cr users, Facebook boasts India as one of its major markets. The recent breach can further make situation difficult for the company in one of is major markets. However, will the proactive ground taken by the company this time be able to move the ball in its corridor, will be something interesting to watch.