Purpose – The purpose of this paper is to investigate the association of lack of awareness and human factors and the association of lack of awareness and significant attacks that threat computer security in higher education. Design/methodology/approach – Five human factors and nine attacks are considered to investigate their relationship. A field research is conducted on Greek employees in higher education to identify the human factors that affect information security. The sample is consisted of 103 employees that use computers at work. Pearson correlation analysis between lack of awareness and nine (9) computer security risks is performed. Findings – Examining the association of lack of awareness with these attacks that threat the security of computers, all nine factors of important attacks exert significant and positive effect, apart from phishing. Considering the relationship of lack of awareness to human factors, all five human factors used are significantly and positively correlated with lack of awareness. Moreover, all nine important attacks, apart from one, exert a significant and positive effect. Research limitations/implications – The paper extends understanding of the relationship of the human factors, the lack of awareness and information security. The study has focused on employees of the Technological Educational Institute (TEI) of Athens, namely, teachers, administrators and working post-graduate students. Originality/value – The paper has used weighted factors based on data collection in higher education to calculate a global index for lack of awareness, as the result of the weighted aggregation of nine (9) risks, and extends the analysis performed in the literature to evaluate the effectiveness of security awareness in computer risk management.