At least two of the vulnerabilities are currently being attacked in the wild so it s imperative that Windows users and administrators treat these patches with the highest possible priority. Of the six bulletins in the July batch of patches, three are rated critical, Microsoft s highest severity rating. The vulnerabilities could allow remote code execution if a user opened a specially crafted QuickTime media file using Internet Explorer that uses the ActiveX control. This vulnerability is currently being exploited in the. wild!
Source: https://threatpost.com/microsoft-plugs-critical-windows-ie-vulnerabilities-071409/72892/