iOS 10.3 update prompts for Mac local account password

[nabla]

Hi all,

following the recent update to iOS 10.3, my iPhone 6S first asked me for my usual iCloud password (which I presumably entered correctly; at least I got no error message on that one).

A rather strange thing happened immediately afterwards: I was prompted for a local account password of one of my iMacs (referenced to by its hostname). Unfortunately I did not take a screenshot in that moment, and since I knew the password, there were no further problems.

But does anybody know what the mechanism behind this is, or where it is documented?
The iMac in question (recently updated to macOS 10.12.4) is signed in to the same iCloud account, so there is probably the connection. But I had not heard of such a password query before, and it felt a bit weird that iOS would ask for the password of a local Mac account.

Thanks
nabla

 

[cswifx]

Hi all,

following the recent update to iOS 10.3, my iPhone 6S first asked me for my usual iCloud password (which I presumably entered correctly; at least I got no error message on that one).

A rather strange thing happened immediately afterwards: I was prompted for a local account password of one of my iMacs (referenced to by its hostname). Unfortunately I did not take a screenshot in that moment, and since I knew the password, there were no further problems.

But does anybody know what the mechanism behind this is, or where it is documented?
The iMac in question (recently updated to macOS 10.12.4) is signed in to the same iCloud account, so there is probably the connection. But I had not heard of such a password query before, and it felt a bit weird that iOS would ask for the password of a local Mac account.

Thanks
nabla

Was your phone in any way connected to the Mac?

 

[nabla]

Was your phone in any way connected to the Mac?

Not in that moment (the iOS update was OTA). However in general, I have the phone connected to the Mac about once a week for iTunes sync and backup.

 

[davidrichter]

A friend of mine told me a few weeks ago, this happened to him. To be honest, i did not believe him. I had no idea why and how the ios device should have known the local mac password.

 

[gtmac]

This happened on my wife's phone and I'll be honest I was annoyed because it seemed like a platform jump. I don't want to use Mac credentials to authenticate to iOS.

 

[Mlrollin91]

I had the complete opposite. After updating my MBA from 10.12.3 to 10.12.4 it asked for my iCloud password (fine thats normal) but then it asked for my iPhone passcode. I thought that was extremely odd. The only reason I can think of was because of 2FA. But you would think it would have asked for the 6 digit code.

 

[cswifx]

I had the complete opposite. After updating my MBA from 10.12.3 to 10.12.4 it asked for my iCloud password (fine thats normal) but then it asked for my iPhone passcode. I thought that was extremely odd. The only reason I can think of was because of 2FA. But you would think it would have asked for the 6 digit code.

If you use iCloud Keychain it may ask for your phone's passcode, because that's what it uses to encrypt your keychains (correct me if I'm wrong).