Security Checks

Verify SSL certificate chain

openssl s_client -connect -CAfile /usr/local/etc/openssl/cert.pem

You should see verify return:1 for each certificate in the chain.

Host header injection

Read about it here.

curl -i --header "Host:"

Your site is vulnerable if appears in the results.


Check if your SPF record is valid. Enter your domain here.


Very few sites have this right now.

dig +dnssec

See how to interpret the results.

Published October 26, 2015 · Tweet

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All code examples are public domain.
Use them however you’d like (licensed under CC0).