Can a SHA-1 hash be all-zeroes?
Yes, it’s just incredibly unlikely. I.e. one in 2^160, or 0.00000000000000000000000000000000000000000000006842277657836021%.
sha1
Check if my SSL Certificate is SHA1 or SHA2
Use the Linux Command Line Use the command line, as described in this related question: How do I check if my SSL Certificate is SHA1 or SHA2 on the commandline. Command Here’s the command. Replace www.yoursite.com:443 to fit your needs. Default SSL port is 443: openssl s_client -connect www.yoursite.com:443 < /dev/null 2>/dev/null \ | openssl … Read more