Looks like 2.4.0 build failed due to OpenSSL 1.1.x. Looks like you submitted upstream ticket, would you meanwhile build 2.4.0 with OpenSSL 1.0?
It BuildRequires pkcs11, which uses 1.1. We're discussing alternatives.
This bug appears to have been reported against 'rawhide' during the Fedora 26 development cycle. Changing version to '26'.
This package has changed ownership in the Fedora Package Database. Reassigning to the new owner of this component.
I have just pushed out openvpn-2.4.1-1 to F25 and F26. The F25 build is against OpenSSL v1.0 and F26 against mbed TLS. The F26 build have an additional patch to allow connecting to servers with weaker RSA keys (less than 2048 bits) and SHA1 + RIPE160 hashing algorithms. This should make the feature gap smaller. The F26 build of openvpn-2.4.1-1 is also sent to F27/Rawhide. However, the Fedora build of mbed TLS does not enable PKCS#11 support. So that is still an issue.
*** This bug has been marked as a duplicate of bug 1391544 ***