New Excel 0-day being exploited
Symantec is reporting that there is an exploit in the wild for an Excel 2007 and Excel 2007 SP1 zero-day remote code execution vulnerability (other versions may be affected as well). There's not a lot of publicly available information about the trojan or the vulnerability. Symantec is saying that the vulnerability is being exploited by a variant of the Mdropper trojan, which they are calling Trojan.Mdropper.AC. There are no patches for this yet (which is part of the definition for 0-day, so duh).
SecurityFocus says the following about how you can be affected:
Successful exploits may allow attackers to execute arbitrary code with the privileges of the user running the application. Failed exploit attempts will result in a denial-of-service condition.
Basically this means just to be careful about Excel files you open. If you don't trust the source, don't open it.
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