Does the Jade check the existence of a change address in the output of a transaction? about jade HOT 3 CLOSED

Makes sense, I forgot the Jade asks the user to confirm the fee 🤦‍♂️ Thank you :)

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Actually, based on this comment, it seems SingleSig/regular MultiSig change does not need to be confirmed by the user (I was checking MultiSig Shield change).

In that case, can a malicious computer omit the change address completely causing the user to burn the change they should have gotten?

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At the moment, no - it does not verify or mandate the presence of a change output. (It is possible [albeit unlikely] that there really is no change.)

So Jade will ask the user to confirm every output - other than those verified as change.
It then, as a final step before signing, asks the user to confirm the fee - this is calculated on the hardware as sum(inputs) - sum(outputs) - so while your suggested attack is possible the user would have to confirm a suspiciously large fee.

I suppose if there is no change output we could add a warning message on that final 'confirm fee' screen - but then that could be confounded by the malicious app adding a very small change output ...

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