Takeover risk

Smartling subdomain takeover.

A subdomain still pointing at a Smartling account that no longer exists is not untidy. It is claimable.

What it looks like

A subdomain on your domain has a CNAME pointing at a smartling.com target, and loading it returns Smartling's unclaimed page rather than a working site. The visible signature is text along the lines of "Domain is not configured".

Both signals are needed. A CNAME pointing at Smartling is completely normal when the service is in use. It only matters when the target is no longer claimed.

Why it can be taken over

Translation and localisation proxies leave records behind when the service ends.

What an attacker gets

  • Content served from your subdomain, on your domain, usually with a valid certificate Smartling issues automatically.
  • A phishing address that passes every check a cautious person would run, because it genuinely is your domain.
  • Access to any cookie your main site scopes to the parent domain, which can include session data.

How to fix it

Remove the record. Localised subdomains such as fr. or de. are easy to overlook because nobody in the head office visits them.

Full removal steps for any DNS provider are in the dangling record guide.

Stopping the next one

These appear whenever a hosted service is trialled and dropped, so one cleanup does not settle it. The habit worth building is deleting the DNS record in the same sitting as the cancellation, because those are separate actions and only one is on anyone's mind.

Check yours

See whether anything on your domain points nowhere.

The free subdomain check finds every name still resolving and confirms which targets are unclaimed.

Other services with the same risk

Each has its own detection signature and removal steps.

Surge · WordPress.com · Fastly · Ghost · Amazon CloudFront · Amazon S3

All 24 in this set