Apple Made Sudden Security Changes to its Chips in Fall 2020

Apple made unusual mid-production hardware changes to the A12, A13, and S5 processors in its devices in the fall of 2020 to update the Secure Storage Component, according to Apple Support documents.

a13 bionic mockup
According to an Apple Support page, spotted by Twitter user Andrew Pantyukhin, Apple changed the Secure Enclave in a number of products in the fall of 2020:

Note: A12, A13, S4, and S5 products first released in Fall 2020 have a 2nd-generation Secure Storage Component; while earlier products based on these SoCs have 1st-generation Secure Storage Component.

The Secure Enclave is a coprocessor that is used for data protection and authentication with Touch ID and Face ID. The purpose of the Secure Enclave is to handle keys and other information, such as biometrics, that are sensitive enough to not be handled by the Application Processor. This data is stored in a Secure Storage Component inside the Secure Enclave, which is the specific part that Apple changed last year.

The explanation in Apple's support document suggests, at minimum, that the eighth-generation entry-level iPad, Apple Watch SE, and HomePod mini have different Secure Enclaves compared to older devices with the same chip.

However, there are a number of discrepancies in Apple's support document. Despite Apple explaining that A13 products "first released in Fall 2020 have a 2nd-generation Secure Storage Component," there was no device with an A13 chip "first released in Fall 2020." The last device to be released with an A13 chip was the iPhone SE in February 2020.

If the change was, in fact, made to all newly-manufactured devices with these chips, the affected devices would include the ‌iPhone‌ XR, ‌iPhone‌ 11, ‌iPhone‌ SE, and fifth-generation iPad mini, as well as the newly-released eighth-generation ‌iPad‌, Apple Watch SE, and ‌HomePod mini‌.

a12 a13 s5 secure enclave change
To make matters more confusing, the table listing the multiple versions of the Secure Enclave's storage component in the feature summary omits the S4 chip with a second-generation Secure Storage Component, despite the rubric claiming that such a chip exists. The Apple Watch Series 4 was the only device to contain an S4 chip, and this device was discontinued in September 2019, long before the second-generation Secure Storage Component was implemented in the fall of 2020. It is possible that part of this lack of clarity relates to the fact that the A12 and S4 chips introduced the first-generation Secure Storage Component.

New devices containing the A14 or S6 chip, such as the ‌iPhone‌ 12, ‌iPhone‌ 12 Pro, fourth-generation iPad Air, and Apple Watch Series 6, also have the updated Secure Enclave.

Although the change took place in the fall of 2020, the support document detailing the alteration was published in February 2021. The full PDF version of Apple's Platform Security Guide reveals the difference between the first and second-generation Secure Storage Component:

The 2nd-generation Secure Storage Component adds counter lockboxes. Each counter lockbox stores a 128-bit salt, a 128-bit passcode verifier, an 8-bit counter, and an 8-bit maximum attempt value. Access to the counter lockboxes is through an encrypted and authenticated protocol.

Counter lockboxes hold the entropy needed to unlock passcode-protected user data. To access the user data, the paired Secure Enclave must derive the correct passcode entropy value from the user's passcode and the Secure Enclave's UID. The user's passcode can't be learned using unlock attempts sent from a source other than the paired Secure Enclave. If the passcode attempt limit is exceeded (for example, 10 attempts on iPhone), the passcode-protected data is erased completely by the Secure Storage Component.

This appears to be a countermeasure against password-cracking devices, such as GrayKey, which attempt to break into iPhones by guessing the passcode an infinite number of times, using exploits that allow for infinite incorrect password attempts.

The change appears to have been significant enough for Apple to justify an entire "second-generation" version of the Secure Enclave's storage. It is certainly unusual for Apple to change a component in its chips mid-way through production, but Apple likely deemed the security upgrade important enough to roll it out to all relevant new devices from the fall onwards, rather than just devices with the latest A14 and S6 chips.

Popular Stories

M5 MacBook Pro

Apple Announces New 14-Inch MacBook Pro With M5 Chip

Wednesday October 15, 2025 6:07 am PDT by
Apple today updated the 14-inch MacBook Pro base model with its new M5 chip, which is also available in updated iPad Pro and Vision Pro models. In addition, the base 14-inch MacBook Pro can now be configured with up to 4TB of storage on Apple's online store, whereas the previous model maxed out at 2TB. However, the maximum amount of unified RAM available for this model remains 32GB. Like...
Apple iPad Pro hero M5

Apple Debuts New iPad Pro With M5 Chip, Faster Charging, and More

Wednesday October 15, 2025 6:16 am PDT by
Apple today announced the next-generation iPad Pro, featuring the custom-designed M5, C1X, and N1 chips. The M5 chip has up to a 10-core CPU, with four performance cores and six efficiency cores. It features a next-generation GPU with Neural Accelerator in each core, allowing the new iPad Pro to deliver up to 3.5x the AI performance than the previous model, and a third-generation ray-tracing ...
maxresdefault

Here's Everything Apple Announced Today

Wednesday October 15, 2025 3:54 pm PDT by
We didn't get a second fall event this year, but Apple did unveil updated products with a series of press releases that went out today. The M5 chip made an appearance in new MacBook Pro, Vision Pro, and iPad Pro models. Subscribe to the MacRumors YouTube channel for more videos. We've rounded up our coverage and highlighted the main feature changes for each device below. MacBook Pro M5...
iphone air thickness

Apple Said to Cut iPhone Air Production Amid Underwhelming Sales

Friday October 17, 2025 8:29 am PDT by
Apple plans to cut production of the iPhone Air amid underwhelming sales performance, Japan's Mizuho Securities believes (via The Elec). The Japanese investment banking and securities firm claims that the iPhone 17 Pro and iPhone 17 Pro Max are seeing higher sales than their predecessors during the same period last year, while the standard iPhone 17 is a major success, performing...
HomePod mini and Apple TV

Apple's Next Rumored Products: New HomePod Mini, Apple TV, and More

Thursday October 16, 2025 9:13 am PDT by
Apple on Wednesday updated the 14-inch MacBook Pro, iPad Pro, and Vision Pro with its next-generation M5 chip, but previous rumors have indicated that the company still plans to announce at least a few additional products before the end of the year. The following Apple products have at one point been rumored to be updated in 2025, although it is unclear if the timeframe for any of them has...
Vision Pro M5 Announcement

Apple Updates Vision Pro With M5 Chip, Dual Knit Band, and 120Hz Support

Wednesday October 15, 2025 6:14 am PDT by
Apple today updated the Vision Pro headset with its next-generation M5 chip for faster performance, and a more comfortable Dual Knit Band. The M5 chip has a 10-core CPU, a 10-core GPU with Neural Accelerators, and a 16-core Neural Engine, and we have confirmed the Vision Pro still has 16GB of RAM. With the M5 chip, the Vision Pro offers faster performance and longer battery life compared...
14 inch MacBook Pro Keyboard

New 14-Inch MacBook Pro Has Two Key Upgrades Beyond the M5 Chip

Thursday October 16, 2025 8:31 am PDT by
Apple on Wednesday updated the 14-inch MacBook Pro base model with an M5 chip, and there are two key storage-related upgrades beyond that chip bump. First, Apple says the new 14-inch MacBook Pro offers up to 2× faster SSD performance than the equivalent previous-generation model, so read and write speeds should get a significant boost. Apple says it is using "the latest storage technology," ...
MacBook Pro M5 Screen

New MacBook Pro Does Not Include a Charger in the Box in Europe

Wednesday October 15, 2025 6:59 am PDT by
The new 14-inch MacBook Pro with an M5 chip does not include a charger in the box in European countries, including the U.K., Ireland, Germany, Italy, France, Spain, the Netherlands, Norway, and others, according to Apple's online store. In the U.S. and all other countries outside of Europe, the new MacBook Pro comes with Apple's 70W USB-C Power Adapter, but European customers miss out....
airpods max 2024 colors

AirPods Max 2: Everything We Know So Far

Tuesday October 14, 2025 8:43 am PDT by
Apple's AirPods Max have now been available for almost five years, so what do we know about the second-generation version? According to Apple supply chain analyst Ming-Chi Kuo, the new AirPods Max will be lighter than the current ones, but exactly how much is as yet known. The current AirPods Max weigh 0.85 pounds (386.2 grams), excluding the charging case, making it one of the heavier...
macbook pro blue

Apple's M5 MacBook Pro Imminent: What to Expect

Tuesday October 14, 2025 4:35 pm PDT by
Apple is going to launch a new version of the MacBook Pro as soon as tomorrow, so we thought we'd go over what to expect from Apple's upcoming Mac. M5 Chip The MacBook Pro will be one of the first new devices to use the next-generation M5 chip, which will replace the M4 chip. The M5 is built on TSMC's more advanced 3-nanometer process, and it will bring speed and efficiency improvements. ...

Top Rated Comments

mtneer Avatar
59 months ago
I wonder if this was in response to a major hardware security breach? Does that mean that devices released before the patch are now vulnerable?
Score: 18 Votes (Like | Disagree)
Serban55 Avatar
59 months ago
Thank you Apple
Score: 14 Votes (Like | Disagree)
mtneer Avatar
59 months ago

everything old become vulnerable.
The article says that the cutoff is "Fall 2020".. that's 6 months ago. We aren't talking about age-old vintage devices here..
Score: 8 Votes (Like | Disagree)
Realityck Avatar
59 months ago
I’m glad Apple is very proactive with hardware based security improvements.
Score: 6 Votes (Like | Disagree)
0924487 Avatar
59 months ago

He’s too busy saving $0.05 per iPhone by not including the charger until the guise of “saving the planet!”.
It’s more like $5 per charger, which isn’t insignificant.
Score: 6 Votes (Like | Disagree)
Serban55 Avatar
59 months ago

I wonder if this was in response to a major hardware security breach? Does that mean that devices released before the patch are now vulnerable?
everything old become vulnerable.
Score: 3 Votes (Like | Disagree)