Connecting to an SSID without provding password

[macmacmacr]

I am running Yosemite and my Macbook pro is able to connect to an SSID without me providing a password. I deleted /Library/preferences/SystemConfiguration/ folder which should clear all of my WIFI preferences. When I checked, it did clear all my preferred SSID's information. I connected to a password protected SSID which I connected to before expecting no connection and the Macbook pro connected without me providing a SSID Password and having no information in my "Preferred networks".

Can anyone tell me how to determine where it is getting the WiFI password? This issue should not occur as any Macbook Pro could be directed to connect to any wifi.

 

[DeltaMac]

Did you remember to both remove your favorite networks, if they still exist in the Preferred Networks box.
Also, un-check the box "Remember Networks this computer has joined".

Any network logins are stored in iCloud, and the system, both used by Keychain Access.

You can look up your network name in your Keychain Access app.
Any network that you have connected should be listed there, along with the password. You can simply delete individual network entries.
The next time you connect, the network should need new login information.
(There's probably a step to remove that login from your iCloud keychain, but I don't know how to do that)

Bottom line - your system (and your iCloud) keeps track of login information, because you have provided that information previously. It doesn't share that information to anyone else - (no one else connects, if there is no previous connection.
So, you are safe from connecting to other, random, secured wifi networks. (And YOUR protected wifi network does not allow no-password access, either)

 

[komatsu]

And even for users not using iCloud - a completely formatted MacBook will still connect to an SSID because wireless passwords are also stored on the NVRAM chip of the MB.

 

[DeltaMac]

I don't believe that wifi passwords are stored in NVRAM, other than one time to connect (which would not indicate that it is stored in NVRAM, either)
Do you have a reference or source that lists anything about that?

However, even if that is true, then you could clear that with a simple NVRAM/PRAM reset, correct?

 

[komatsu]

No "official" source but read link below.

From personal experience, OS X wireless passwords do get retained even after a full format.

And yes a PRAM reset is meant to clear it.

https://forums.macrumors.com/threads/air-keeps-wifi-password-even-if-disk-wiped.1204822/

 

[DeltaMac]

Erm..
That really only shows a guess (by one person) about where wireless passwords might be retained. Nothing definitive about NVRAM there, although it sounds reasonable, even if not factual.
I have googled this before, and have not found any information about that. Not that the info does not exist, but I just haven't found the right way to search for it.
So, until I see something that is just a little more solid, NVRAM ain't it (IMHO, for what it's worth)

 

[Weaselboy]

And even for users not using iCloud - a completely formatted MacBook will still connect to an SSID because wireless passwords are also stored on the NVRAM chip of the MB.

If you have previously used Internet recovery and entered the wifi password during that process, it is true that password will be saved in NVRAM for the next time you use Internet recovery (command-option-r), but that password is not made available to the OS for logging in to that same wifi network like OP is experiencing.

Sounds like OP has iCloud Keychain sync on and the password is coming back over from another device.

 

[macmacmacr]

Erm..
That really only shows a guess (by one person) about where wireless passwords might be retained. Nothing definitive about NVRAM there, although it sounds reasonable, even if not factual.
I have googled this before, and have not found any information about that. Not that the info does not exist, but I just haven't found the right way to search for it.
So, until I see something that is just a little more solid, NVRAM ain't it (IMHO, for what it's worth)

I believe that the Macboo pro is somehow directly accessing the keychain information. The WIFI password still existed in the key chain but I do not understand what is referring to the value sinvce the network preference infomration have been cleared.
[doublepost=1490070849][/doublepost]I have also noticed another problem when deleteing the first SSID entered. When I try to delete the first SSID entered after clearing /Library/preferences/SystemConfiguration/ folder I get an error message "Preference erros" "There was an error in the network preference"

 

[macmacmacr]

Erm..
That really only shows a guess (by one person) about where wireless passwords might be retained. Nothing definitive about NVRAM there, although it sounds reasonable, even if not factual.
I have googled this before, and have not found any information about that. Not that the info does not exist, but I just haven't found the right way to search for it.
So, until I see something that is just a little more solid, NVRAM ain't it (IMHO, for what it's worth)

If I have deleted the /Library/preferences/SystemConfiguration/ folder and I also tried to delete the specific SSID key but it kept returnung. Where is it getting the information?

 

[FreakinEurekan]

If I have deleted the /Library/preferences/SystemConfiguration/ folder and I also tried to delete the specific SSID key but it kept returnung. Where is it getting the information?

Keychain

 

[macmacmacr]

The keychain is where the Mac OS keeps all of its internal passwords like the SSID for WIFI is kept there on Yosemite. When I removed the key for the SSID in the keychain I am trying to delete, it still remains in the network preferences.