Iranian Society of Cryptology The ISC International Journal of Information Security 2008-2045 18 1 2026 01 29 Detecting Fake Accounts Through Generative Adversarial Network in Online Social Media 35 47 231870 10.22042/isecure.2025.505399.1215 EN Jinus Bordbar Department of Computer Engineering, Islamic Azad University, Shiraz Branch, Shiraz, Iran Mohammadreza Mohammadrezaei Department of Computer Engineering, Ramh.C., Islamic Azad University, Ramhormoz, Iran. Saman Ardalan Institute for Medical Informatics and Statistics, University of Kiel, Kiel, Germany. Mohammad Ebrahim Shiri Department of Computer Sciences, Faculty of Mathematics and Computer, Amirkabir University of Technology, Tehran, Iran. Journal Article 2025 03 12 Online social media is integral to human life, facilitating messaging, information sharing, and confidential communication while preserving privacy. Platforms like Twitter, Instagram, and Facebook exemplify this phenomenon. However, users face challenges due to network anomalies, often stemming from malicious activities such as identity theft for financial gain or harm. This paper proposes a novel method using user similarity measures and the Generative Adversarial Network (GAN) algorithm to identify anomalies (fake nodes) in user accounts in a large-scale social network while handling imbalanced data issues. Despite the problem's complexity, the method achieves an AUC rate of 80\% in classifying and detecting fake accounts. Notably, the study builds on previous research, highlighting advancements and insights into the evolving landscape of anomaly detection in online social networks. The findings of this study contribute to ongoing advancements in fake account detection, offering a hopeful solution for securing online spaces against fraudulent activities and anomaly detection in social networks. https://www.isecure-journal.com/article_231870_0c561707c1dcc69251dcb54af019175a.pdf