Using mod_setenvif
:
SetEnvIf Request_URI "^/about$" allow=yes AuthType Basic AuthName "Password Required" AuthUserFile /var/www/webinterface/.htpasswd Options +FollowSymLinks Order Deny,Allow Satisfy any Deny from All Require valid-user Allow from env=allow
→ bottom part blocks entire content except if you are logged in or if allow=yes
, which is only set if the request uri is the about site.