Weak security

This is NOT an iPhone problem; it is a problem with your router settings.

A "Weak Security" notification means that your Wi-Fi router is not configured correctly. There is a new feature in iOS 14 that checks and displays a message if your router is not using the most up-to-date security settings. Note that your router has always had weak security, you just didn’t know about it until now. 

See this Apple support article for how to configure it correctly—>Recommended settings for Wi-Fi routers and access points - Apple Support, specifically the section headed Security. And don't forget to configure your range extenders (if any) also!

Note also that weak security does not interfere with using Wi-Fi, it is just a warning. Your Wi-Fi should still work normally, and, if it doesn’t, it is not because of the weak security message.

Wi-fi security mostly depends on the access point you are using and your device's ability to use the correct access point's security protocols.

I am guessing you saw a message on the iPhone saying you have weak security, something like "WPA/WPA2 (TKIP) is not considered secure".

Since I don't know what kind of hardware (access point-router) you're using or even if it is YOUR hardware, we don't know if it can be configured to use newer, more secure protocols.

Absent this information, you should connect in priority to wi-fi access points that use the WPA3 or WPA2 (AES) protocols. Those are the most secure protocols, in that order. Avoid older protocols like WEP and WPA as well. While not perfect, WPA2 will give you a reasonably high level of security. If you can, choose WPA2 (AES) over WPA2 (TKIP).

You should NEVER connect to networks without security, open (no password) or unsecured.

Next step: configure your access point correctly or purchase a newer, more secure one.

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