There are various threats that militate against SMEs in developing economies. However, most SMEs fall on the conservative "TV News Effect" of most-publicized cyber-threats or incidences, with disproportionate mitigation measures. This paper endeavors to establish taxonomy of threat agents to fill in the void. Various fuzzy similarity measures based on multi-attribute decision-making techniques have been employed in the evaluation. The taxonomy offers a panoramic view of cyber-threats in assessing mission-critical assets, and serves as a benchmark for initiating appropriate mitigation strategies.