>>> wget https://vampire.york.ac.uk/resources/release-5/vampire-5.0-linux.tar.gz

--2025-04-18 10:52:39--  https://vampire.york.ac.uk/resources/release-5/vampire-5.0-linux.tar.gz
Resolving vampire.york.ac.uk (vampire.york.ac.uk)... 144.32.124.80, 2001:630:61:17c::1:50
Connecting to vampire.york.ac.uk (vampire.york.ac.uk)|144.32.124.80|:443... connected.
ERROR: cannot verify vampire.york.ac.uk's certificate, issued by ‘CN=Sectigo ECC Organization Validation Secure Server CA,O=Sectigo Limited,L=Salford,ST=Greater Manchester,C=GB’:
  Unable to locally verify the issuer's authority.
To connect to vampire.york.ac.uk insecurely, use `--no-check-certificate'.

>>> openssl s_client -connect vampire.york.ac.uk:443 -showcerts

Connecting to 144.32.124.80
CONNECTED(00000005)
depth=0 C=GB, ST=York, O=University of York, CN=vampire.york.ac.uk
verify error:num=20:unable to get local issuer certificate
verify return:1
depth=0 C=GB, ST=York, O=University of York, CN=vampire.york.ac.uk
verify error:num=21:unable to verify the first certificate
verify return:1
depth=0 C=GB, ST=York, O=University of York, CN=vampire.york.ac.uk
verify return:1
---