In today’s technologically advanced world, the escalating prevalence of phishing attacks necessitates an urgent exploration of effective countermeasures. This study delves into the crucial investigation of how self-regulation influences phishing susceptibility, while also examining the mediating role of information processing and the moderating influence of financial knowledge. A comprehensive survey was meticulously crafted, targeting 370 recent university graduates. The collected data underwent rigorous analysis using Hayes’ PROCESS macro, unveiling a mediated moderation model. The findings reveal that self-regulation does not directly predict phishing susceptibility. However, information processing, whether systematic or heuristic, significantly impacts phishing susceptibility. Additionally, information processing serves as a mediator, connecting self-regulation to phishing susceptibility. Notably, the interaction between systematic information processing and financial knowledge emerged as a significant determinant of phishing susceptibility. By establishing a comprehensive mediated moderation model, this study provides invaluable insights for individuals and organizations seeking to bolster their defenses against phishing attacks. Furthermore, it emphasizes the vital role of financial knowledge and employees’ heuristic information processing in mitigating cyber threats. This research serves as a crucial scientific contribution, offering compelling evidence that proactive management of contributing factors can effectively mitigate the escalating threats posed by phishing attacks.