Severity Rating: Important
Revision Note: V3.0 (December 12, 2014): Rereleased bulletin to announce the reoffering of Microsoft security update 2986475 for Microsoft Exchange Server 2010 Service Pack 3. The rereleased update addresses a known issue in the original offering. Customers who uninstalled the original update should install the updated version of 2986475 at the earliest opportunity.
Summary: This security update resolves four privately reported vulnerabilities in Microsoft Exchange Server. The most severe of these vulnerabilities could allow elevation of privilege if a user clicks a specially crafted URL that takes them to a targeted Outlook Web App site. An attacker would have no way to force users to visit a specially crafted website. Instead, an attacker would have to convince them to visit the website, typically by getting them to click a link in an email message or Instant Messenger message that takes them to the attacker's website, and then convince them to click the specially crafted URL.

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