INTRODUCTION Need to make perfect, undetectable of MIFARE Classic® 1K Cards ? Many access control systems / RFID readers are now able to detect "Chinese Magic" tags by sending the "Unlock Command" (0x40 / 0x43). If the badge replies, it is flagged as an imposter / clone and rejected. These "Gen2a" badges allow the UID to be set one time only - and after that - the tag never responds to magic commands. This allows you to make undetectable, perfect clones. Once the UID has been set, the tag acts as a normal card. You can change the data of the card as many times as required - we've tested up to 10,000 read/write cycles. Remember: This badge's UID can only be set one time. These tags are red and in key ring form for convenience. Technical Specifications Feature Information Notes Chipset MIFARE Classic® Compatible Memory Size 1K UID Size 4 Byte UID Modifiable ✔️ One time only Chip Generation Gen 2 OTW (Gen2a) Chipset Generation Guide Write Capabilities UID Modifiable Unlock Required DirectWrite / Block 0 One Time Write Notes ✔️ ✔️ ✔️ UID can only be modified once! Device Compatibility Compatibility UID R/W Config Notes Flipper Zero ✔️ ✔️ ✔️ Proxmark / iCopy-X ✔️ ✔️ ✔️ Android & iOS ✔️ ✔️ ✔️ MTools recommended LibNFC ✔️ ✔️ ✔️ ChameleonUltra ✔️ Requires MTools Hands on: See the card in action The MIFARE Classic® Compatible 1K UID One-Time-Write can be used with several tools: LibNFC - change UID To update the UID of the badge, simply write the dump contents to the badge. nfc-mfclassic w a u /tmp/1K.dmp Proxmark - change UID To update the UID of the badge, simply write the dump contents to the badge. When using wrbl - you are directly modifying the card's configuration. Ensure that all data is correct including BCC - otherwise you will brick your card. hf mf wrbl --blk 0 -k FFFFFFFFFFFF -d 11223344440804006263646566676869 # Where 11223344 is the UID, 08 is the BCC Unbricking "Soft-bricking" refers to when a magic card has been configured in a way that prevents it from being detected. Ways of soft-bricking tags include: Incorrect BCC Incorrect SAK Incorrect ATQA Incorrect ATS Incorrect ACL (Access Control) Values Some "soft-brick" situations can be resolved with special commands. If your MIFARE Classic® Compatible 1K UID Modifiable is "soft-bricked", you can try recovering it with the following methods: With Proxmark / iCopy-X hf 14a config --atqa force --bcc ignore --cl2 skip --rats skip # for 1k hf mf wrbl --blk 0 -k FFFFFFFFFFFF -d 11223344440804006263646566676869 --force hf 14a config --std hf 14a reader Via external reader/writer and MTOOLS Select the "UID Changer" function in MTools, select "bricked" and run the task IMPORTANT: Lab401 cannot provide refunds under any circumstances for cards that were 'bricked' due to incorrect configurations.
