I have got a lot of domains. I use basic monitoring script, which checks expiration date of ssl certificate. But a few of my domains use default cloudflare cert.

How to determine and reject domains which use cloudflare built-in SSL certificate?

  • 1
    What are you starting with? You have noted that you are using curl on Linux, how are you using that? Have you already extracted the certificate, or even the certificate chain? – Law29 Jun 29 '18 at 11:48

You could just make a simple bash script like:


x=$(openssl x509 -in cert.pem -text | grep -i cloudflare)

if [ "$x" != "" ]; then
  # code for rejecting
  # code for ok
  • If you replace 'cert.pem' with $1 then you can just issue ./script.sh name-of-cert.pem – Jonas Bjork Jun 29 '18 at 11:56

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