The global COVID-19 pandemic has led educational institutions to shut down and adopt e-learning practices through computer-mediated communication. An unanticipated switch of online classes from face-to-face classes isolates students from social groups and teachers, causing online disinhibition. Therefore, this paper investigates factors influencing university students' toxic disinhibition behavior in online classrooms, WhatsApp groups, and Telegram groups. Also, social isolation has been used as a moderating variable to identify whether social isolation strengthens or weakens the proposed association. The research holds the basis of "Social Cognitive Theory" and "Theory of Planned Behavior." The data from 506 university students have been collected for analysis. The proposed framework and research hypotheses have been assessed via PLS-SEM using Smart PLS software. Findings from the study show that toxic behavior victimization, attitude, subjective norms, and behavioral control are factors that positively & significantly affect toxic disinhibition online. Furthermore, motives and self-efficacy showed an insignificant influence on toxic disinhibition. Additionally, toxic disinhibition significantly & positively affects toxic behavior. At last, social isolation is likely to have a moderation effect on the variables. Hence, the research yields guidance on reducing toxic disinhibition online. Further, implications and recommendations are discussed at the end of the study.