This attack could pose a serious security threat. You should take immediate action to stop any damage or prevent further damage from happening.
This signature detects a vulnerability in Microsoft Excel which may result in remote code execution.
Microsoft Excel is a spreadsheet application that is part of the Microsoft Office suite.
Excel is prone to a remote code-execution vulnerability when parsing a specially crafted Excel ('.xls') file. This issue is triggered when the vulnerable application parses an '.xls' file containing a crafted 'DbOrParamQry' record.
Attackers can exploit this issue by enticing victims to open a malicious Excel file.
Successful exploits can allow attackers to execute arbitrary code with the privileges of the user running the application.
The vendor has released an advisory and updates. Please see the references for details.