Phishing Prevention Focusing on Certificates and Input Forms: PoC as Browser Extensions

Phishing attacks against consumers have become increasingly sophisticated, necessitating effective real-time detection methods. This study analyzes the characteristics of phishing sites, focusing on certificate validity periods and input forms. Based on a dataset of 1,047 unique fake website URLs collected from multiple sources, we found that 89.8% of the phishing sites had certificate validity periods of 90 days or less. To effectively prevent this threat, we developed a proof-of-concept (PoC) browser extension that leverages certificates and input forms as key indicators for real-time phishing detection. The PoC extension achieved an detection rate of 93.9%. Comparative analysis showed that our approach outperformed several existing solutions, including Google Safe Browsing, in detecting phishing sites. While the proposed method demonstrates high effectiveness, we also discuss its limitations. This study demonstrates the potential of approaches leveraging certificates and input forms for real-time detection, offering a simple yet effective countermeasure.