Proxmark3 community

Danz

Contributor

From: Dubai

Registered: 2015-10-24

Posts: 98

Jakcom R3 ring Reader compatiblity issue

Hello everyone,

Been a while since I come back here, but always coming back with interesting stuff haha,
I have a new issue with my work card, where we use normal HID 125khz to enter building and office,

I have the following :
1- Proxmark3 updated with the latest software (Iceman and official)
2- Jackom ring, http://www.jakcom.com/ins/R3/JAKCOM_R3.html , I think they have T55,S50,NXP (3 chips) I have used this ring 3 years ago and worked perfectly in other projects.
3- T55/S50 combo card,

So the issue is, I have read my original work card with HID read, clone it on combo card and jackom ring, using HID clone command,
both combo card and ring open my office building (black small reader on doors), but only combo card can pass building reader gate (different type).

now since two cloned item analysis have dual HF and LF, there is no collusion why gate reader does not detect the ring at all (no error sound),

analysis :
I used HID read command, both ring and combo card came back with my original HID wiegned format ID.
I used T55 detect, for both ring and combo card, ONLY combo card get detected, I dumped it with blocks of T55 command, where I tried to write block by block on the ring, but for some reason It doesn't write one block randomly (like checksum not matching), I tried to check if ring is password protected, none, even when I manage to get exact match of blocks between ring and combo card, ring does not read under HID read command.

Am pretty frustrated on why it only works at office reader, any insights on what to do will be helpful (poking Iceman here )

Thanks,

Danz

Contributor

From: Dubai

Registered: 2015-10-24

Posts: 98

Re: Jakcom R3 ring Reader compatiblity issue

as follow up I found one difference, Ring offset is 31 , while the cloned card is 32,

Trying to change offset manually, will change all data from t55 dump .. I believe this could be why the main gate reader doesn't recognize the ring.