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steven

Contributor

Registered: 2020-12-15

Posts: 3

Can't write on FUID

Hi everyone

I recently try to write on FUID tags that used to work before (I mean new tags of the same type), but unfortunately I updated the firmware and now it doesn't work anymore.

It was working with firmware v4.9237

So, when I try to write on the tags with hf mf restore, I get

Cmd error: 04
Write Block error
Write to block X w key B ( fail )

I noticed that it try to write with key B, so I tried to write to some block with hf mf wrbl  and specified use of key A (hf mf wrbl -a ...) and it works with the fuid's defaults key (FFFFFFFFFFFF).
With that workaround, I can change block 0 and others blocks, but I don't get how it works with key's blocks. Can I simply rewrite them with new keys values ?

Writing to gen1a tags works fine by the way (so I don't think the problem is related to the proxmark).

I don't get why it stopped working with the same commands. Maybe the way theses commands changed by I don't found any info about this.

Maybe the ability to specify the key to use to the restore command could resolve this problem...

If someone have any idea to help my I'll by very pleased !

[edit] Ok so I get my response and the new tag works when i write the right key on block's key.Luckily for myself my tag don't have much infos to write by maybe that problem that seems to be a bug need to be fixed because writing an entire tag block by block can be a little painfull.

Last edited by steven (2021-07-24 12:20:17)

iceman

Administrator

Registered: 2013-04-25

Posts: 9,468

Website

Re: Can't write on FUID

a bit old, try latest source or release.  Not that it might resolve your issue but its always better to be on latest.

steven

Contributor

Registered: 2020-12-15

Posts: 3

Re: Can't write on FUID

Ok, sorry I did not been enough clear, the problem occur with latest release (v4.13441). I recompiled today and I still have this problem. I tried also with -ka option, so it's like on restore mode none key works.

But anyway, i also have the option of downgrading to v4.9237, that fixe the problem.

iceman

Administrator

Registered: 2013-04-25

Posts: 9,468

Website

Re: Can't write on FUID

I'm afraid I don't understand but if you found a solution  Good!