Proxmark3 is the swiss-army tool of RFID, allowing for interactions with the vast majority of RFID tags on a global scale. Originally built by Jonathan Westhues, the device is now the goto tool for RFID Analysis for the enthusiast. Iceman repository is considered to be the pinnacle of features and functionality, enabling a huge range of extremely useful and convenient commands and LUA scripts to automate chip identification, penetration testing, and programming.
When they say to read the manual, read the manual.
Github repo for the MIT RFID ring kit. Includes greyprints for fabbing your own rings.
An open source set of libraries and tools written in Python for interacting with RFID and NFC chips.
A brief synopsis on the construction of a weapon which can fry RFID chips, including those of passports and ID cards. There are no schematics, just a list of the principles used in the design. You'll need knowledge of electronics to make sense of it and apply them in a practical manner.
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