Introduction

This article is about forensic investigation of Internet Explorer. This is cover about investigating Internet Explorer history, cache, cookies, favorites. Lets take a look at index.dat file

Index.dat

Microsoft’s Internet Explorer has two primary areas of interest. One is “index.dat†database file which is used by the web browser and the browser cache. index.dat is in the format of MSIECF (Microsoft Internet Explorer Cache File Format). The index.dat file contains information of visited URLs including the accessed and modified time, the location of cache directory, HTTP headers and so on and so fourth. Almost every software uses IExplorer for displaying information and for connecting over internet. Programs like skype, Live messenger, etc uses IE. So the history of accessed urls of those applications are also stored in index.dat.

The location of index.dat file

C:\Documents and Settings\%username%\Local Settings\Temporary Internet Files\Content.IE5  


Windows vista and 7:  
C:\Users\%username%\ AppData\Local\Microsoft\Windows\Temporary Internet Files\Content.IE5```  

Now lets start investigating the index.dat file. I will use a tool name [pasco](http://sourceforge.net/projects/fast/files/Pasco/) by Foundstone which is very old but still used is many Live forensic distros. Here is a example  

./pasco -d index.dat  

As you see this will give the out put in the following format.  

![Image](http://i.imgur.com/LyvHYYi.png)  
As this is not clear it is better to get a output to a file simple by using ./pasco > outputfile  

There is another tool which we extract information in a organized manner. It is called [msiecfexport](http://code.google.com/p/libmsiecf/).  
Here is an example:  

![Image](http://i.imgur.com/RxEdraJ.png)  
So you can clearly view the index.dat file.   

##Cache  

Next we'll investigate the cache files. Cache files are stored locally as a result of the user's web browsing. These files are stored in  

C:\Documents and Settings\%username%\Local Settings\Temporary Internet Files\Content.IE5

Windows vista and 7:
C:\Users\%username%\AppData\ Local\Microsoft\Windows\Temporary Internet Files\Content.IE5```

I will take an example from msiecfexport.

Record type : URL  
Offset range : 67968 - 68224 (256)  
Location : temp:http://thepaperwall.com/wallpapers/girls/big/big_45fb5c22369e1c5d517f0282bd9250105f407e77.jpg  
Primary time : Feb 05, 2013 04:26:07.030000000  
Secondary time : Feb 05, 2013 04:26:02.830616500  
Filename : big_45fb5c22369e1c5d517f0282bd9250105f407e77[1].jpg  
Cache directory index : 1 (0x01)(OV08Z8PA)  

As you see the file “big_45fb5c22369e1c5d517f0282bd9250105f407e77[1].jpg
†is locally stored in cache directory “OV08Z8PAâ€. So the actual location is C:\Users\%username%\AppData\
Local\Microsoft\Windows\Temporary Internet Files\Content.IE5
/OV08Z8PA/big_45fb5c22369e1c5d517f0282bd9250105f407e77[1].jpg

Well of course this is the file :p

Image
Here is the ouput of the cache by pasco:
URL temp:http://thepaperwall.com/wallpapers/girls/big/big_45fb5c22369e1c5d517f0282bd9250105f407e77.jpg 02/04/2013 20:26:02 02/04/2013 20:26:07 big_45fb5c22369e1c5d517f0282bd9250105f407e77[1].jpg OV08Z8PA

You can again see “OV08Z8PA†is our cache sub directory.

Cookies

Cookies can be found on
```
Windows XP
C:\Documents and Settings\%username%\ Cookies

Windows Vista and 7:
C:\Users\%username%\AppData\Roaming\Microsoft\Windows\Cookies```

Cookies are normally in text format and we cannot understand anything.
s_vsn_skypeallprod_1 3876974264756 skype.com/ 1600 2798871808 31012227 2587949280 30277570 * s_vi [CS]v1|288542BB05010F82-4000012C80000C57[CE] skype.com/ 1024 505403008 30645652 3108158896 30278524 * SC CC=:CCY=:LC=en:TM=1359888053:TS=1359888053:TZ=:VER=0/6.1.0.129/272 skype.com/ 1536 1767549056 30351564 3897935152 30278138 *

I will use a tool called galleta which is a awesome tool release by McAfee labs.

Image
Cookie File: C:\Users\Osanda\AppData\Roaming\Microsoft\Windows\Cookies\un0wn@skype[2].txt SITE VARIABLE VALUE CREATION TIME EXPIRE TIME FLAGS skype.com/ s_vsn_skypeallprod_1 3876974264756 Thu Jan 31 14:52:34 2013 Tue Jan 31 14:52:34 2023 1600 skype.com/ s_vi [CS]v1|288542BB05010F82-4000012C80000C57[CE] Tue Feb 5 08:42:25 2013 Sun Feb 4 08:42:41 2018 1024 skype.com/ SC CC=:CCY=:LC=en:TM=1359888053:TS=1359888053:TZ=:VER=0/6.1.0.129/272 Sun Feb 3 10:40:39 2013 Mon Feb 3 10:40:53 2014 1536

Now you can nicely view the contents in the cookie file.

Favorites

Investigating Favorites will also be interesting in IE. By the user’s bookmarks we can identify what kind of interests he owns.

In windows XP  
C:\Documents and Settings\%username%\Favorites  


Windows vista and 7:  
C:\Users\%username%\FavoritesIn windows XP  
C:\Documents and Settings\%username%\Favorites  

Windows vista and 7:  
C:\Users\%username%\Favorites```  

Favorites are in different folders by default and suppose I added google.lk to favorites we can clearly see “Google.url† 
Here is an example:  

[DEFAULT]
BASEURL=http://www.google.lk/
[{000214A0-0000-0000-C000-000000000046}]
Prop3=19,2
[InternetShortcut]
URL=http://www.google.lk/
IDList=
IconFile=http://www.google.lk/favicon.ico
IconIndex=1```

Conclusion

Even though you erase history it won’t be deleted and is still their on the index.dat file. There are third party tools which actually erase the index.dat. But remember any file can be recovered in seconds and some third party tools leave traces. So the best would be to shred the index.dat file manually.