> I have couple of unique domain names that I have open in my browser which have unique and non-guessable DNS names, which are crawled by some bots today. Even though I never shared them in any way with anyone! The only way they could be exposed for crawling is by my DNS provider leaking the DNS traffic to some shady third-party.
Not true.
They may be connecting directly by IP (it's typically not possible to determine if they did just from access logs). The web (or other application) server may also leak the name when connected to.
If you use TLS, which is likely, your domain names would leak through the certificate transparency logs.
...and there are surely more leak vectors than the above, so it's far from certain that the crawlers you see found their target by sniffing your DNS requests.
Not true.
They may be connecting directly by IP (it's typically not possible to determine if they did just from access logs). The web (or other application) server may also leak the name when connected to.
If you use TLS, which is likely, your domain names would leak through the certificate transparency logs.
...and there are surely more leak vectors than the above, so it's far from certain that the crawlers you see found their target by sniffing your DNS requests.