If you are getting a cloudflare warning the site that you are attempting to connect to is probably being targeted by a DDS attack. Give it a little time and you will be able to try again and get back on.

I'm not aware of a CloudFlare security issue. I use CloudFlare's free DNS service and haven't noticed any problems.

Can CloudFlare cause security issues for users who are accessing a site that uses CloudFlare?

I'm having a security issue on another site, but unsure of the root cause.

I really don't know much about CloudFlare and google didn't really give me any finite answers.

TIA if you have anything to share!