When opening the page https://account.web.cern.ch/account browsers display warnings saying that there are problems with the site certificate.

The problem is that the certificate is identifying the site as "*.cern.ch", which is not valid for "account.web.cern.ch", as the wildcard character does not match the extra level (i.e. xyz.cern.ch is ok, xyz.web.cern.ch is not).

This is actually a redirection problem, as users should not be redirected to .web.cern.ch. The problem does not show up with, for example, http://account.cern.ch or http://cern.ch/account.

The site's certificate is valid, and users can ignore this warning (and select "Continue").