Cloudflare-SSLDetector
CloudFlare SSL detector web crawler
About this crawler
Cloudflare-SSLDetector is a web crawler identified by the regular-expression pattern Cloudflare-SSLDetector in the User-Agent request header. It is categorised as scanner. Use the regex above to detect, log, allow, or block Cloudflare-SSLDetector traffic in your web server, CDN edge rules, or robots.txt.
Block-rate · top 25k sites
0.065%
Technical details
- Name
- Cloudflare-SSLDetector
- Pattern
Cloudflare-SSLDetector- Tags
- scanner
- Reference
- https://developers.cloudflare.com/ssl/origin-configuration/ssl-tls-recommender/
- Added
- 2024/12/17
- rDNS suffixes
.cloudflare.com- Instances
- 1 known sample(s)
rDNS verification (FCrDNS)
Verify a request is genuinely Cloudflare-SSLDetector with forward-confirmed reverse DNS: the client IP's PTR record must end in one of the suffixes below and a forward A/AAAA lookup of that hostname must return the same IP. UA strings alone are spoofable; FCrDNS is not.
.cloudflare.com
Sample User-Agent strings
Cloudflare-SSLDetector
Block this crawler
robots.txt — disallow Cloudflare-SSLDetector:
User-agent: Cloudflare-SSLDetector
Disallow: /
Apache .htaccess — return 403:
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} Cloudflare-SSLDetector [NC]
RewriteRule .* - [F,L]
Nginx — return 403 inside a server block:
if ($http_user_agent ~* "Cloudflare-SSLDetector") {
return 403;
}
← back to all crawlers