Microsoft has released 14 patches to plug 34 vulnerabilities in its August security update.
Eight of the 14 bulletins were rated "critical" including security advisory MS10-056, which resolves four privately reported vulnerabilities in Microsoft Office.
According to the Microsoft Security Response Team, the most severe vulnerabilities could allow remote code execution if a user opens or previews a specially crafted RTF e-mail message.
"An attacker who successfully exploited any of these vulnerabilities could gain the same user rights as the local user. Windows Vista and Windows 7 are less exploitable due to additional heap mitigation mechanisms in those operating systems," Angela Gunn, Security Response Communications Manager, wrote in Microsoft's advisory blog.
Other critical and high-priority bulletins resolve holes in Microsoft's MPEG Layer-3 audio codec, Cinepak Codec in Windows Media Player, the .NET Framework and Silverlight.
Six other patches were rated important, with two being Windows Kernel updates.
Microsoft recommends that customers test and deploy all security updates as soon as they can.