Why does Global Protect Portal shows port 80 Connection successful via telnet ?

• Why does the Global Protect Portal port 80 shows connection successful? 
  Example:
  
  
  
  Some online vulnerability scanners can detect port 80 open on firewalls, which may cause a report signifying a potential gateway for a man-in-the-middle attack (MITM).

• This is due to the redirection support feature added where the firewall always redirects HTTP traffic to HTTPS.
• HSTS header enforces the usage of HTTPS at all times, even though the port connection shows successful.
• Alternatively, you can implement a security policy to block/deny TCP port 80/service-http by creating the policy with a services object defining TCP port 80 (https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000ClEhCAK)
  
  
  

Does the PAN provide options for HTTP to HTTPS Redirect on Globalprotect Portal?

How to Configure GlobalProtect Portal Page to be Accessed on any Port

HSTS Additional info