Protection of personal information in a modern smartphone does not begin with unlocking the screen, but with ensuring the security of the screen itself. SIM-Owners of Xiaomi and Redmi devices often neglect installation PIN-But this kind of carelessness can lead to serious problems: If an attacker extracts your SIM card and inserts it into another phone, they will gain access to the number, which paves the way for confirming transactions in banks and recovering passwords on social networks.
Changing the standard factory password to a unique code is a basic step of cyber hygiene that every user must follow. In the MIUI shell that is installed on Redmi smartphones, the security setting process is implemented as conveniently as possible, although it has its own features that distinguish it from “pure” Android. In this article, we will discuss in detail the algorithm of actions that will allow you to reliably protect your phone number from unauthorized access.
It is important to understand that the password SIM-The card and the screen unlock password are two different layers of protection, and even if your phone is securely protected by biometrics, the SIM card itself can remain vulnerable without a separate security. PIN-We're going to look not only at the code change process, but also at the nuances of working with the code. PUK-code, as well as modern methods of protection through binding to the Mi Account.
Why do you need an installation? PIN-code SIM-map
Substantive function PIN-The code is to prevent your SIM card from being used on other devices without your knowledge. Imagine if you lost your smartphone or stole it. If the SIM card doesn't have a password, the thief can simply move it into his device and start accepting it. SMS With confirmation codes to log into your banking applications. PIN-The code blocks this possibility by requiring you to enter digits immediately after turning on any device that inserts your SIM.
In addition, many users forget that standard factory passwords (usually 0000 or 1234) are easy to guess. Attackers often try these combinations in the first place. Changing the code to a customized combination significantly improves security. In Xiaomi devices, this mechanism is integrated into the overall security system, which allows you to flexibly configure password request settings.
⚠️ Note: Three times injected infidel PIN-code-lock SIM-It'll take a map to unlock. PUK-The code that is on the plastic card that you give away when you buy a SIM card!
It is not just a matter of locking the screen of a smartphone. Current data theft techniques allow you to bypass some types of protection if physical access to the SIM card is not limited. Therefore, activating protection at the carrier level (via SIM) is a critical measure, which creates an additional barrier that makes life much more difficult for potential fraudsters.
Preparing for a password change: what you need to know
Before you start changing your security settings, you need to make sure you have all the data you need on hand. PIN-If you've never changed a factory password, try the standard combinations of 0000, 1111 or 1234, which are often set by the default carriers. If none of them fit, contact your carrier's salon or find the envelope that sold the SIM card.
It is also important to make sure that your Redmi smartphone is charged with enough to avoid accidental reboot during the setup process.Although changing the password is quick, suddenly turning off the device when writing new data to the SIM card memory can theoretically cause a failure.It is recommended to have a battery charge of at least 30-40% before starting any manipulation of the system security settings.
Remember or write down a new password in a safe place right after it's created. Human memory often fails, and after a week you may forget which combination you chose. Using complex but personal numbers is the best option. Don't use dates of birth or obvious sequences that are easy to pick up by brute force.
☑️ Preparation for password change
Step-by-step instructions: how to change PIN-code
The process of changing the password in the MIUI shell may vary slightly depending on the firmware version, but the overall algorithm remains the same for most Xiaomi and Redmi models. First you need to go to the security settings menu. To do this, open the Settings app and find the section responsible for protecting the device. In newer versions of the interface, it is often hidden in the Passwords and Security submenus.
After entering the security section, find the item “Privacy” or immediately “Protection”. SIM-Here you will see a list of SIM cards installed, if there are two. Choose the one you want to change the password for. PIN-A code to confirm the right to change the settings, and only after successful authorization will a menu open where you can activate or change your password request.
To change the code, select the option "Change". PIN-You'll need to enter the old code and then double-enter the new one. Make sure you don't miss a typo when you re-enter. Once confirmed, the system will save the changes, and from that point on, every time you reboot your phone or retrieve your SIM card, you'll need a new digit combination.
What to do if the menu is not available?
Set up biometric unlocking SIM-map
Owners of modern Xiaomi smartphones can appreciate the convenience of unlocking a SIM card using a fingerprint or face, which allows you not to enter a digital code every time you turn on your phone, if you have already unlocked the smartphone itself with biometrics, which significantly speeds up the process while maintaining a high level of protection.
To activate this function, go to the same "Protection" menu. SIM-You'll find a fingerprint unlock switch or something like that, activate it and follow the instructions on the screen, and the system will ask you to put your finger on the scanner for confirmation, and then when you turn on the device, if the SIM card requires you to. PIN, Your phone automatically uses your biometrics to unlock your phone.
But it's important to remember the limitations. SIM-The card only works if you unlocked the phone first. If you rebooted your smartphone and haven't entered the pattern lock or password on the device, the system will still require you to enter it. PIN-This is done for security reasons, because biometrics are stored in a secure module, which is only accessible after initial authorization.
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Use different fingers to unlock your phone and SIM-cards if your model supports the assignment of specific fingerprints for different actions, although in the standard MIUI It is usually a single biometric profile.
Table: Comparison of SIM protection methods
Understanding the differences between different security layers will help you choose the best security strategy. Below is a comparison table that illustrates the advantages and disadvantages of different approaches to protecting your SIM card on Redmi devices.
| Protection method | Level of security | Convenience | Risks. |
|---|---|---|---|
| Factory PIN (0000) | Low. | High. | Easy to pick up. |
| Unique. PIN-code | High-pitched | Average. | Forget the code. |
| Biometrics (fingerprint) | High-pitched | Very high. | Scanner failure |
| Lack of protection | Absent. | Maximum. | Theft of a number |
As you can see from the table, the failure to protect is the most convenient, but carries critical risks. PIN-This balances security between data security and speed of access to the device in everyday use.
What to do if you forget PIN-code (PUK)
A situation where the user forgets PIN-The code and the SIM card locks are quite common, and in this case the phone will ask for it. PUK-Personal Unblocking Key is an eight-digit code that serves as an emergency key for resetting. PIN-You can find it on a plastic card that came with a SIM card when you bought it, and it's usually hidden under a protective layer.
If your plastic card is lost, don’t panic. PUK-The code is linked to your number and stored by the carrier, and you can find it in several ways: through your personal account on the operator's website, in a mobile application or by calling support. For identification, you may be asked to name your passport details or code word, if it has been installed.
It is important to be careful when entering PUK-You only have 10 attempts if you type in the wrong code ten times. PUK, The SIM card will be permanently blocked, and it will be impossible to restore it - you will have to buy a new SIM card with a number saved (reissue procedure.
⚠️ Warning: Never try to guess. PUK-If you're not sure about the code, you'll have to contact the operator first if you're not sure about the code, if you're not sure about the SIM chip, you'll have to get in touch with the operator.
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PUK-The code is the only way to restore access to the blocked SIM-card without visiting the communication salon, so keep it in a safe place apart from the phone.