Mac OS X users experienced the highest number of vulnerabilities. Windows Vista users experienced fewest and the fewest High severity vulnerabilities. Red Hat Enterprise Linux 5 Desktop and Mac OS 10.5 (Leopard) had the most vulnerabilities in January through March of 2008. Mac users experienced highest number vulnerabilities as well as the highest high severity vulnerabilities while Windows Vista experienced the most and fewest vulnerabilities in Q1 2008 – Client OS Vulnerability Scorecard. The report is available at the Q1 report by NVD.com and by clicking here.”]
Source: https://www.csoonline.com/article/2136949/which-desktop-os-had-the-most-vulns-in-q1-2008-.html