iPhone users know that Apple has imposed many restrictions on the iOS system downgrade verification channel.
Every time Apple pushes a new version of the iOS system, it will close the verification channel of the previous system and do not allow downgrading operations.
Nowadays, Apple's action is also getting faster and faster, basically a week after the release of the new version, it closed the verification channel of the previous version.
And now, Apple seems to have quietly opened the back door to this restriction.
Recently, some netizens found that Apple actually opened the iOS 14.1 (18A8395) system verification channel for the iPhone XS Max National Bank Edition.
Users with this model can now downgrade back to iOS 14.1.
However, not all iPhone XS Max models can be downgraded.
Through the netizen test, it was found that only the iPhone XS Max model of the two networks of the National Bank of China can be downgraded to iOS 14.1.
The IPhone XS Max version of the National Bank of China is mostly a three-network model, and the two-network version is really rare.
If the small partner using the iPhone XS Max version of the Bank of China has the need to downgrade, you can download the firmware now and try to downgrade the system.
You can enter the fruit powder club public account, reply to the keyword "downgrade" to obtain the download address of the iOS 14.1 firmware file.
Remember to back up your data before downgrading to avoid losing important data during the downgrade process.
It's unclear why Apple only opened the downgrade channel for the iPhone XS Max model.
Many users have been expecting Apple to completely open up this restriction and allow users to downgrade themselves.
Developers have also always wanted to break through Apple's restrictions and achieve a free downgrade of iOS.
As early as September 2019, foreign researchers found that through an iPhone vulnerability, it can be used to make long-term effective jailbreak tools and implement iOS version downgrading.
The vulnerability, called Checkm8, is different from a software vulnerability in the general sense of the word, which exists in hardware and is discovered by security personnel in the Bootrom (Secure Boot ROM) of the iPhone.
In addition, the scope of iPhone models affected by this vulnerability is also very large.
Because the Checkm8 exists on all iOS devices equipped with A5-A11, it covers all iPhones released by Apple from 2011 to 2017, including the iPhone 4S-iPhone X, a total of eight models.
As soon as the incident was exposed, some developers developed an iOS downgrade tool called ReRa1n through the vulnerability, and successfully downgraded the iPhone 5s to iOS 10.3.3.
Theoretically, ReRa1n can be downgraded at will between iOS 6 and iOS 13 with almost no restrictions.
However, the tool stopped updating in early 2020 for unknown reasons.
This very popular tool has gradually faded out of people's sight.
Many users still very much hope that Apple can open the downgrade channel, and users can freely choose to stay on any system version of their iPhone.
From the user's point of view, the upgrade of the iOS system is two-sided.
On the one hand, Apple can push new features to users faster, which is more conducive to the construction of the ecosystem, and for users, they can also experience the new features they joined at the first time.
On the one hand, there are many people who use the iPhone for several years, and with the upgrade of the system version, the old iPhone running the latest system will definitely be "inadequate".
Therefore, it may be relatively appropriate to give different users the right to choose.
Do you want Apple to open up the iOS downgrade channel?
For more information about the use of Apple device knowledge and skills and to inquire about the warranty, you can pay attention to my WeChat public account: cxkj-001 (fruit powder club).