← All Status Codes
526
Invalid SSL Certificate
☁️ Cloudflare
High Risk
📖 What Is HTTP 526?
Cloudflare-specific. The origin SSL certificate is invalid, expired, self-signed, or the hostname does not match. Cannot establish a trusted connection.
🛡️ Security Implications
Invalid certificates break the chain of trust. A self-signed cert may indicate a compromised or improperly configured origin.
🔍 Common Causes
Self-signed certificate on origin, expired certificate, wrong hostname in certificate, incomplete certificate chain.
🔧 How to Fix
Install a valid SSL certificate from a trusted CA. Use Cloudflare Origin CA certificates. Ensure the full certificate chain is installed.
🖥️ How to Check
curl -I -o /dev/null -w "%{http_code}" https://example.com