A simple tool to get subdomain from SSL Certificate
Usage of ./certsubs:
-d string
Only get subdomains end with this domain.
-p string
Ports to connect, separate with comma. (default "443")
-t int
Threads to use. (default 5)
./certsubs domain.com
cat domains.txt | ./certsubs -p 8080,443,8888 -t 10 -d domain.com