Performance and Configuration Mistakes

Outdated protocol support represents both security and performance mistakes. Continuing to support SSLv3, TLS 1.0, or TLS 1.1 exposes sites to known vulnerabilities while preventing adoption of performance improvements. These older protocols lack modern security features and enable downgrade attacks. Browser vendors actively deprecate older protocols, meaning continued support provides no compatibility benefit while maintaining security risks.

Weak cipher suite selection compromises security and may impact performance. Supporting export-grade ciphers, RC4, or DES-based algorithms enables attacks despite HTTPS implementation. Conversely, overly restrictive cipher requirements may exclude legitimate users with older devices. The balance requires understanding current security recommendations and user demographics. Regular reviews ensure cipher configurations remain appropriate as the security landscape evolves.

Missing security headers fail to maximize HTTPS security benefits. HTTP Strict Transport Security (HSTS) prevents downgrade attacks by forcing browser HTTPS usage. Without HSTS, users remain vulnerable to initial HTTP connections before redirects. OCSP stapling improves performance by eliminating certificate revocation checks. Content Security Policy headers provide additional protections against content injection. These headers require careful configuration but significantly enhance security posture.

Session management misconfigurations negate performance optimizations available in modern TLS implementations. Disabled session resumption forces complete handshakes for every connection, adding latency and computational overhead. Inadequate session cache sizing causes frequent cache evictions, reducing resumption effectiveness. Load-balanced environments require shared session storage or properly configured session tickets. These optimizations become crucial for sites with many repeat visitors.