Why do I see other portals' URLs in my SSL certificate?
We use Group SSL (Secure Socket Layer) certificates to establish a secure, encrypted connection between your browser and our servers. Since these certificates are applied to many domain-mapped portals and considering all those sub-domains are having their CNAME pointed to desk.cs.zohohost.com, you will be able to see a string of portal URLs in your SSL certificate.
Nevertheless, this is no cause for worry in your Zoho Desk account.