Archive for May 25, 2020

Monday, May 25, 2020

Grocery Shopping With Guided Access

Ole Begemann:

Problem: Face ID doesn’t work with face masks. You have to type in your passcode all the time during grocery shopping to check your shopping list.

Solution: Open your shopping list app and activate Guided Access. Tada!


Guided Access limits your device to a single app and lets you control which features are available.


Go to Settings > Accessibility, then turn on Guided Access.


On an iPhone X or later, triple-click the side button.

On the plus side, this keeps the phone unlocked, so you don’t have to type your passcode every time you take it out of your pocket. The downside is that there’s no way to turn off the display to prevent accidental input or battery drain.


Update (2020-05-25): You need to enter your Guided Access passcode to exit Guided Access, and then enter your full passcode to pay with Apple Pay.

unc0ver Jailbreak Tool for iOS 13.5

Frank McShan (Hacker News):

The team behind the “unc0ver” jailbreaking tool for iOS has released version 5.0.0 of its software that claims to have the ability to jailbreak “every signed iOS version on every device” using a zero-day kernel vulnerability by Pwn20wnd, a renowned iOS hacker.


As for security, unc0ver’s website says it utilizes “native system sandbox exceptions” so that “security remains intact while enabling access to jailbreak files.”


Update (2020-07-09): Brandon Azad (tweet, Hacker News):

At 3 PM PDT on May 23, 2020, the unc0ver jailbreak was released for iOS 13.5 (the latest signed version at the time of release) using a zero-day vulnerability and heavy obfuscation. By 7 PM, I had identified the vulnerability and informed Apple. By 1 AM, I had sent Apple a POC and my analysis. This post takes you along that journey.

Solving the “Miracle Sudoku” in Prolog

Jason Kottke:

The solver himself calls it “a work of sublime genius” and “one of the most extraordinary puzzles we’ve ever seen”. It’s fascinating listening to him slowly uncover different aspects of the puzzle — watching him methodically figure out the 3s was genuinely thrilling.

Ben Congdon (via Hacker News):

Since Prolog is a declarative language, writing a Sudoku solver is remarkably concise. In essence, all the programmer needs to do is define the constraints of the game, and Prolog is smart enough to find solutions[…]


The cool thing about this code is that it works both as a Sudoku solver and as a Sudoku generator. You can query it with a partially solved board, and it will find all valid solutions.


Surprisingly, there are only 72 solution boards that meet the Miracle Sudoku constraints.