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Comment by tlrobinson

8 years ago

If I'm understanding correctly, that list would include not only the 3,438 domains with content that triggered the bug, but every Cloudflare customer between 2016-09-22 and 2017-02-18.

Can we trust it was only those domains?

  • Not really. If a site is using Cloudflare protection for only some of their subdomains they do not show on this list even if the site itself is in the alexa top 10k sites.

    And of course all other sites that are not in alexa 10k are not in this list (if they are not on some other lists used, you can see the source of lists in the README of the Github repo).

No. Only Cloudflare customers using a subset of features of the SSL proxy service are impacted.

Cloudflare has a lot of customers who only use the free DNS service, for example.

  • Careful. It appears that any Cloudflare client who was sending HTTP/S traffic through their proxies is affected. A small subset of their customers had the specific problem that triggered the bug, but once triggered, the bug disclosed secrets from all their web customers.

    You're not exposed if you never sent traffic through their proxies; for instance, if you somehow only used them for DNS.

    • I suspect there are a large number of Cloudflare customers that only use their DNS. I have a couple of domains in this category.

      The DNS service is essentially free. It's an upgrade from most registrars' built-in DNS. It's a pretty robust solution, really -- global footprint, DNSSEC, fully working IPv6, etc.

      My point is, the actual number of impacted customers was much smaller than the entire set of Cloudflare customers. There are lists in this thread that still reference hundreds of thousands (millions?) of sites, and that's just wrong.

      (I agree on your first point though; I was confused about the nature of the proxy bug at first).