Now Patched 'Sign in With Apple' Bug Left Users Open to Attack

Researcher Bhavuk Jain in April discovered a critical Sign in With Apple vulnerability that could have resulted in a takeover of some user accounts. The bug was specific to third party apps that used Sign in With Apple and didn't implement additional security measures.

SigninwithApple e1590865553423
Jain notes that Sign in With Apple works by authenticating a user through a JWT (JSON Web Token) or a code that's generated by Apple's server. Apple then gives users the option to share either the email tied to their Apple ID or a private relay email address,which creates a JWT that's used to log in a user.

Jain then discovered that once JWTs for both Apple ID emails and private relay email addresses were requested and the token's signature was verified using Apple's public key, it "showed as valid." Should the bug have not been discovered, a JWT could be created and used to gain access to one's account.

In an interview with The Hacker News, Jain spoke about the severity of the bug:

The impact of the this vulnerability was quite critical as it could have allowed a full account takeover. Many developers have integrated Sign in with Apple since it is mandatory for applications that support other social logins. To name a few that use Sign in with Apple - Dropbox, Spotify, Airbnb, Giphy (now acquired by Facebook).

According to Jain, Apple conducted an investigation and concluded that no accounts were compromised using this method before the vulnerability was patched. Jain was paid $100,000 by Apple under its Apple Security Bounty Program for reporting the bug.

Top Rated Comments

SBlue1 Avatar
51 months ago
100,000? Well deserved. :)
Score: 13 Votes (Like | Disagree)
B4U Avatar
51 months ago
Are we getting numb with the constant SW issues that Apple is having lately?
Score: 11 Votes (Like | Disagree)
Peace Avatar
51 months ago
I’m getting burned out on timmys security problems .

windows is looking better
Score: 10 Votes (Like | Disagree)
I7guy Avatar
51 months ago

I’m getting burned out on timmys security problems .

windows is looking better
Windows is better? Sure windows is as tight as a drum as far as that goes.

Just keep patching them Timmy.
Score: 7 Votes (Like | Disagree)
cmaier Avatar
51 months ago

I don't care.

I'm done updating.

I'm sick and tired of my phone being artificially slowed.

I'm back to using Linux for things that need to be secure, like banking, etc.
You know this wasn’t a bug in the client software or operating system, right?
Score: 5 Votes (Like | Disagree)
konqerror Avatar
51 months ago

If it was unexploited and has been patched, there's not much of a story here… except to other businesses that might consider Sign In With Apple.
Bugs are a symptom, not the flaw. The constant stream of problems coming out from Apple shows their software development and QA processes are severely flawed.
Score: 5 Votes (Like | Disagree)

Popular Stories

maxresdefault

Apple Announces 'Let Loose' Event on May 7 Amid Rumors of New iPads

Tuesday April 23, 2024 7:11 am PDT by
Apple has announced it will be holding a special event on Tuesday, May 7 at 7 a.m. Pacific Time (10 a.m. Eastern Time), with a live stream to be available on Apple.com and on YouTube as usual. The event invitation has a tagline of "Let Loose" and shows an artistic render of an Apple Pencil, suggesting that iPads will be a focus of the event. Subscribe to the MacRumors YouTube channel for more ...
Apple Silicon AI Optimized Feature Siri

Apple Releases Open Source AI Models That Run On-Device

Wednesday April 24, 2024 3:39 pm PDT by
Apple today released several open source large language models (LLMs) that are designed to run on-device rather than through cloud servers. Called OpenELM (Open-source Efficient Language Models), the LLMs are available on the Hugging Face Hub, a community for sharing AI code. As outlined in a white paper [PDF], there are eight total OpenELM models, four of which were pre-trained using the...
iOS 18 Siri Integrated Feature

iOS 18 Rumored to Add These 10 New Features to Your iPhone

Wednesday April 24, 2024 2:05 pm PDT by
Apple is set to unveil iOS 18 during its WWDC keynote on June 10, so the software update is a little over six weeks away from being announced. Below, we recap rumored features and changes planned for the iPhone with iOS 18. iOS 18 will reportedly be the "biggest" update in the iPhone's history, with new ChatGPT-inspired generative AI features, a more customizable Home Screen, and much more....
Apple Vision Pro Dual Loop Band Orange Feature 2

Apple Cuts Vision Pro Shipments as Demand Falls 'Sharply Beyond Expectations'

Tuesday April 23, 2024 9:44 am PDT by
Apple has dropped the number of Vision Pro units that it plans to ship in 2024, going from an expected 700 to 800k units to just 400k to 450k units, according to Apple analyst Ming-Chi Kuo. Orders have been scaled back before the Vision Pro has launched in markets outside of the United States, which Kuo says is a sign that demand in the U.S. has "fallen sharply beyond expectations." As a...
iPad And Calculator App Feature 1

Apple Finally Plans to Release a Calculator App for iPad Later This Year

Tuesday April 23, 2024 9:08 am PDT by
Apple is finally planning a Calculator app for the iPad, over 14 years after launching the device, according to a source familiar with the matter. iPadOS 18 will include a built-in Calculator app for all iPad models that are compatible with the software update, which is expected to be unveiled during the opening keynote of Apple's annual developers conference WWDC on June 10. AppleInsider...