A 27 year old Indian security Researcher Bhavuk Jain grabs a whopping Rs75 lakh from Apple for finding a Zero Day vulnerability in the Sign in using Apple account authentication.
The vulnerability could have allowed hackers to break into an Apple User’s account who use third party apps to log in using Dropbox, Spotify, Airbnb and Giphy.
Jain is a engineer and holds bachelor’s degree in electronics and communication.
“This bug could have resulted in a full account takeover of user accounts on that third party application irrespective of a victim having a valid Apple ID or not,” Jain said in a statement on Saturday.
“For this vulnerability, I was paid $100,000 by Apple under their Apple Security Bounty programme,” he announced.
Jain is a mobile app developer. He is self employed and works full time as bug bounty hunter.
After Jain finding the bug and submitting it to Apple’s bug bounty programme, Apple has pached the bug since then.
How Bhavuk Jain Find the Bug
The Sign with Apple works using OAuth 2.0
“There are two possible ways to authenticate a user by either using a JWT (JSON Web Token) or a code generated by the Apple server. The code is then used to generate a JWT,” he explained.
In the second step, while authorizing, Apple gives an option to a user to either share the Apple Email ID with the third party app or not.
If the user decides to hide the Email ID, Apple generates its own user-specific Apple relay Email ID.
“Depending upon the user selection, after successful authorization, Apple creates a JWT which contains this email ID which is then used by the 3rd party app to login a user,” said Jain.
He discovered that he could get JWTS for any email ID from Apple and when the signature of these tokens is verified using Apple’s public key, it showed valid.
“This means an attacker could forge a JWT by linking any Email ID to it and gaining access to the victim’s account,” Jain noted.