Windows can find/show them through the netsh command.
Note that there is a difference between "weak password" and "weak WiFi password".
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Weak service password found
Description
A service on this device has a weak or default password. This is very dangerous situation, because factory-default usernames and passwords are often used by hackers and cybercriminals.
Catalogue ID HNS-WEAK-PASS
Username: ●●●●●●●●admin
Password: ●●●●●●●●admin
Details
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admin/admin (displayed under the dots) were the default user/password only used by my TP-Link router which I have changed long back. Also, "Details" about this error explains that this user/password should be changed on router's admin interface - System Tools -> Password. So it is router password and not the wifi password.
I just don't know how to tackle this wrong pickup of user/password values.
Regards.