Vivo key apex bug

I found a bug with my vivokey Apex today. It scared the crap out of me but I did manage to get it fixed (I think) I went to go set-up bitwarden to use u2f and selected the fido2 applet by mistake, I went to uninstall it and dropped my phone during uninstall. It said failed but the item was removed from the list so I then tried to install the u2f and failed to install because of space on the chip. Weird since I just removed my fido2 applet and know I had some extra space. Removed my NDEF to make room and no fix. I tried to reinstall my NDEF and it now fails to install also. Nothing will install at this point, I tried a bunch of applets with nothing working. It for sure has some garbage in memory, so I try to reinstall the original failed fido2 applet and it installs! Like instantly installs, it normally take a while, but this time it was instantly. I then remove it successfully and can install applets again like normal. I thought I’d bricked my implant for like 15 minutes. If I had waited a few days between the failed remove and trying too install something again I would have forgotten what I did and be very confused and angry.

So heads up! If it fails to remove, reinstall it and try to remove again or you’ll get locked out of a chunk in memory. My curiosity then lends me to ask, can I view any other possibly half installed applets? For all I know I might have a few on there I’m just unaware of, that are taking up memory for no reason.


This is most likely due to fidesmo trying to keep track of what you’ve installed. There’s no built in feature to list installed applets, so they keep track of it. And things like this happen when you have 2 sources of truth.

If you however really found a way to make parts of the memory unusable for ever, that would’ve been a serious issue. This seems to be an avoidable issue, not with the apex but fidesmos software design.


Avoidable sure, but still an issue. Even if it’s fidesmos fault it’s part of the vivokey ecosystem.

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This is absolutely a known issue with Fidesmo and we have lodged this complaint with them multiple times.

We are working on an app called Apex Manager that will be able to actually detect this by using a combination of the Fidesmo SDK and our own approach to querying the chip for applications on board. If there is a mismatch we will be able to highlight it and instruct you on how to remedy the situation.

We also launched a new app called Free Memory which will help determine actual memory available on the chip.


I actually saw and tried to install the free memory applet in the middle of having the issue. I got the funny ironic failed to install message. But once I did have it installed I noticed the last of a companion app. It would have been helpful.

The Apex Manager app is still in development, but we will be asking for beta testers soon™