Once the keys are found, the data is displayed in hexadecimal format. For those new to RFID, the most important rule is to watch the "Access Bits." These bits determine whether a sector can be read or written. MCT 2.3.1 includes an "Access Bit Calculator" to help users decode these bits without manual binary conversion.
Only interact with tags you own or have explicit permission to audit. mifare classic tool 2.3.1
MIFARE Classic is an aging technology. Its security relies on the CRYPTO1 algorithm, which has been publicly compromised for years. Tools like MCT 2.3.1 highlight these vulnerabilities by demonstrating how easily data can be cloned or modified if the encryption keys are discovered. It is vital to use MCT responsibly: Once the keys are found, the data is
The tool can compare the data between two different tags or different saves of the same tag to identify where specific values (like a balance or an ID number) are stored. Only interact with tags you own or have
Always create a full dump of a card before attempting to write data. Writing incorrect data to the "Trailer Block" (the last block of any sector) can permanently lock that sector if the keys are overwritten with unknown values.
📍 If MCT says "No keys found," you may need to use external tools like Proxmark3 to crack the keys first, then import them into MCT to perform mobile edits. If you'd like to dive deeper into using this tool: Step-by-step cloning guide (using CUID tags) Troubleshooting device compatibility (NXP vs. Broadcom) Decoding Access Bits (understanding sector permissions) Which of these areas should we explore next?