# Proxmark3 v4.20142 "Blue Ice" Released

> The Blue Ice release adds iClass tear-off attacks, Hitag Mu/8265 support, MIFARE Ultralight AES auth, and smarter autopwn with static encrypted nonce detection.

_2025-03-25_

Version 4.20142 "Blue Ice" of the [Iceman fork](https://github.com/RfidResearchGroup/proxmark3) of the Proxmark3 firmware and client is here. This release brings new attacks, fresh tag support, and a long list of reliability fixes across the LF and HF stacks.

## Highlights
- Added `hf iclass trbl` to run tear-off attacks against iClass cards, plus new special legacy config cards and a simulation function in `hf iclass legrec`, expanding the toolkit for iClass research.
- Added `lf hitag htu` support and `lf em 410x clone --htu` to clone an EM410x ID onto Hitag Mu/8265 transponders, opening up a new generation of LF tags.
- Added `hf mfu aesauth` for MIFARE Ultralight AES authentication, with `hf mfu info` now correctly identifying UL EV1 AES 50pF parts.
- Changed `hf mf autopwn` to detect static encrypted nonces and honor user cancel during key checking, with a new option to use the SPI flash dictionary and a custom suffix.
- Added `hf seos sam` for HID SAM SEOS communications and improved `trace list -t seos` to annotate ISO7816, strengthening SEOS analysis.
- Added `hf 15 slixprotectpage` and initial support for ST25TN tags with signature verification, broadening ISO15693 coverage.
- Moved flash-stored key dictionaries (MIFARE, iClass, T55xx) and configurations to SPIFFS files and extended MIFARE key storage to 4095 keys for far larger on-device dictionaries.
- Fixed DESFire D40 secure channel crypto and `hf mfp info` signature checks on 4-byte UID cards, plus Wiegand decode no longer drops the first bit.

## Contributors
This release landed thanks to [@iceman1001](https://github.com/iceman1001), [@doegox](https://github.com/doegox), [@piotrva](https://github.com/piotrva), [@antiklesys](https://github.com/antiklesys), [@douniwan5788](https://github.com/douniwan5788), [@ANTodorov](https://github.com/ANTodorov), [@nvx](https://github.com/nvx), [@jmichelp](https://github.com/jmichelp), [@trigat](https://github.com/trigat), [@gentilkiwi](https://github.com/gentilkiwi), [@henrygab](https://github.com/henrygab), [@tinooo](https://github.com/tinooo), [@jkramarz](https://github.com/jkramarz), [@onovy](https://github.com/onovy), [@emilyastranova](https://github.com/emilyastranova), [@zxkmm](https://github.com/zxkmm), and others.

Read the [full changelog and downloads on GitHub](https://github.com/RfidResearchGroup/proxmark3/releases/tag/v4.20142).