05/10/2026
Subdomains can be a cybersecurity risk.
If you use subdomains, you might be accidentally giving hackers permission to use your exact website address.
Think about the temporary marketing campaigns, event pages, or third-party software portals you set up in the past.
Usually, companies create a custom web link for these projects, like promo.yourcompany.com
To make it work, that custom link is connected to an external hosting service.
When the project ends, you probably cancel the external hosting subscription to save money.
But the connection rule in your website settings is almost never deleted.
This creates a massive blind spot.
Attackers constantly scan the internet for these abandoned connections.
When they find one, they go to that exact hosting company and register the account name you used to have.
Because your website is still pointing there, the attacker instantly takes control of your official custom link.
They can now send phishing emails to your clients or host scam pages that look completely real.
Your clients will trust the link because it literally uses your actual company name.
If you haven’t done this yet, you need to audit your website DNS records as soon as possible.
Delete any custom links pointing to software or services your business no longer uses.
