OK, thanks,
It turns out there's an additional issue; it appears that Node.js 6.11.2 with the bundled http-parser doesn't work properly with OpenSSL 1.0.1 on EPEL 7. This would also be fixed by requiring RHEL/CentOS 7.4 (since it upgraded to OpenSSL 1.0.2).
I'm trying to figure out what to do here. We can't just put back the http-parser in EPEL unfortunately because the RHEL folks unintentionally released a lower NVR for the official package. If we put ours back, it would supersede RHEL and take them out of support on any package linking against it (which now includes parts of SSSD).
I'm going to spend a little time today trying to figure out if I can fix the OpenSSL 1.0.1 compatibility patch and push out an update that will work with the bundled http-parser for now.