Bulletin Severity Rating:Critical - This critical security update resolves two privately reported and two publicly disclosed vulnerabilities. One of these vulnerabilities could allow remote code execution if a user viewed a specially crafted e-mail using Windows Mail in Windows Vista. The other vulnerabilities could allow information disclosure if a user visits a specially crafted Web page using Internet Explorer and cannot be exploited directly in Outlook Express. For the information disclosure vulnerabilities, users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
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