Mal/HTMLGen-A reported on ESXi 6.7 host

Question

Anyone know why Sophos endpoint software kicks up this message when trying to access an ESXI host by its IP address? 
 
 Sophos endpoint advanced 10.8.3 with core agent 2.2.2 is what is installed on my windows box. 
 I can rebuild any ESXI6.7 u1 or u2 from the official VMware ESXI iso's , tried both modified & standard versions and I get this Sophos message every time when trying to connect to the ESXI host by its IP address. 
 If I use the FQDN of the host , I do not get the message - this happens on all browsers where Sophos endpoint is installed. 
 Any info would be greatly appreciated.

DianneY · Answer

Hello Dam Sam 
 Yes, it is likely that (bad history), or some part of URL assessment has gone wrong even if it's in the reserved range -- that much I don't know of, since that part is with Sophos Labs. 
 There is not customer-facing tool that can analyze URL's at the moment; for now you would have to check with support or Sophos Labs (via URL re-assessment) for categories. You can chime in to this product enhancement suggestion so it gets more visibility with Product Management. 
 As Badrobot suggested, you may whitelist the IP range in your Threat Control Policy under Scanning Exclusions, with exclusion type of "Website" to get past the Mal/HTMLGen-A warning, and also maybe assign a website tag to the IP range if it's being blocked in Web Control (to get past the other blocked message). 
 
 Hope that all helps.