If I'm on 18.7.1, do I still need to upgrade?
https://www.cvedetails.com/version/2021355/Apple-Iphone-Os-1...
seems to be the same as 18.7.2
https://www.cvedetails.com/version/2037518/Apple-Iphone-Os-1...
If I'm on 18.7.1, do I still need to upgrade?
https://www.cvedetails.com/version/2021355/Apple-Iphone-Os-1...
seems to be the same as 18.7.2
https://www.cvedetails.com/version/2037518/Apple-Iphone-Os-1...
Most likely. This is a WebKit issue whose patch is only shipped with iOS 26.2 or iOS 18.7.3 (but that's only available to a subset of iPhone and iPadOS devices).
See: https://support.apple.com/en-us/125885