<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv=Content-Type content="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 11 (filtered medium)">
<style>
<!--
/* Font Definitions */
@font-face
{font-family:Verdana;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman";}
a:link, span.MsoHyperlink
{color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:Arial;
color:windowtext;}
@page Section1
{size:595.3pt 841.9pt;
margin:72.0pt 90.0pt 72.0pt 90.0pt;}
div.Section1
{page:Section1;}
-->
</style>
<!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang=EN-GB link=blue vlink=purple>
<div class=Section1>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>It has been more than a year since Michael Lynn </span></font><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>first</span></font><font
size=2 face=Arial><span lang=EN-US style='font-size:10.0pt;font-family:Arial'>
demonstrated a reliable code execution exploit on Cisco IOS at Black Hat 2005.
Although his presentation received a lot of media coverage in the security
community, very little is known about the attack and the technical details
surrounding the IOS <i><span style='font-style:italic'>check_heaps()</span></i>
vulnerability. This paper is a result of research carried out by IRM to </span></font><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>analy<i><span
style='font-style:italic'>s</span></i>e</span></font><font size=2 face=Arial><span
lang=EN-US style='font-size:10.0pt;font-family:Arial'> and understand the <i><span
style='font-style:italic'>check_heaps()</span></i> attack and its impact on
similar embedded devices. Furthermore, it also helps developers understand security-specific
issues in embedded environments and developing mitigation strategies for
similar vulnerabilities. The paper primarily focuses on the techniques
developed for bypassing the <i><span style='font-style:italic'>check_heaps()</span></i>
process, which has traditionally prevented reliable exploitation of memory-based
overflows on the IOS platform. Using inbuilt IOS commands, memory dumps and
open source tools IRM was able to recreate the vulnerability in a lab
environment. The paper is divided in three sections, which cover the ICMPv6
source-link attack vector, IOS Operating System internals, and finally the
analysis of the attack itself.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>The full paper can be downloaded from:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-US
style='font-size:12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><a href="http://www.irmplc.com/index.php/69-Whitepapers">http://www.irmplc.com/index.php/69-Whitepapers</a><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><strong><b><font size=1 face=Verdana><span style='font-size:
7.5pt;font-family:Verdana'><o:p> </o:p></span></font></b></strong></p>
<p class=MsoNormal><strong><b><font size=1 face=Verdana><span style='font-size:
7.5pt;font-family:Verdana'><o:p> </o:p></span></font></b></strong></p>
<p class=MsoNormal><u1:PersonName u2:st="on"><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'><o:p> </o:p></span></font></p>
</div>
</body>
</html>