Gen.Variant.Koutodoor.6_af5bfd6aae

Dynamic Analysis

Payload

No specific payload has been found.

Process activity

The Trojan creates the following process(es):

%original file name%.exe:2004

The Trojan injects its code into the following process(es):No processes have been created.

File activity

The process %original file name%.exe:2004 makes changes in the file system.

The Trojan creates and/or writes to the following file(s):

%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\desktop.ini (67 bytes)
%System%\drivers\dcdavvx.sys (40896 bytes)
%System%\zpu.dll (53248 bytes)
%System%\djpssp.bat (120 bytes)

Registry activity

The process %original file name%.exe:2004 makes changes in the system registry.

The Trojan creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths]
"Directory" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path4]
"CacheLimit" = "65324"
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache4"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2]
"CacheLimit" = "65324"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\DateTime]
"SID" = "S-1-5-21-606747145-1060284298-839522115-1004"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cookies" = "%Documents and Settings%\%current user%\Cookies"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache2"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Common AppData" = "%Documents and Settings%\All Users\Application Data"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\HideDesktopIcons\NewStartPanel]
"{871C5380-42A0-1069-A2EA-08002B30309D}" = "0"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cache" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files"

[HKLM\System\CurrentControlSet\Hardware Profiles\0001\Software\Microsoft\windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1]
"CacheLimit" = "65324"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Connections]
"SavedLegacySettings" = "3C 00 00 00 0C 00 00 00 01 00 00 00 00 00 00 00"

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "38 C3 2A F0 EA 50 99 68 2D 8C BA 83 5E 96 D8 07"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache1"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3]
"CacheLimit" = "65324"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"MigrateProxy" = "1"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"History" = "%Documents and Settings%\%current user%\Local Settings\History"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache3"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths]
"Paths" = "4"

The Trojan modifies IE settings for security zones to map all local web-nodes with no dots which do not refer to any zone to the Intranet Zone:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"UNCAsIntranet" = "1"

The Trojan modifies IE settings for security zones to map all web-nodes that bypassing the proxy to the Intranet Zone:

"ProxyBypass" = "1"

Proxy settings are disabled:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

The Trojan modifies IE settings for security zones to map all urls to the Intranet Zone:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"IntranetName" = "1"

The Trojan deletes the following value(s) in system registry:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"AutoConfigURL"
"ProxyServer"
"ProxyOverride"

Dropped PE files

There are no dropped PE files.

HOSTS file anomalies

No changes have been detected.

Rootkit activity

The Trojan's driver "%Drivers%\dcdavvx.sys" substitutes a pointer of ParseProcedure function for the object Device.

The Trojan's driver "%Drivers%\dcdavvx.sys" substitutes a pointer of ParseProcedure function for the object Key.

Using the driver "%System%\drivers\dcdavvx.sys" the Trojan controls creation and closing of processes by installing the process notifier.

Propagation

Removals

Remove it with Ad-Aware

1. Click (here) to download and install Ad-Aware Free Antivirus.
2. Update the definition files.
3. Run a full scan of your computer.

Manual removal*

1. Scan a system with an anti-rootkit tool.
   
2. Terminate malicious process(es) (How to End a Process With the Task Manager):

   %original file name%.exe:2004

3. Delete the original Trojan file.
   
4. Delete or disinfect the following files created/modified by the Trojan:

   %Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\desktop.ini (67 bytes)
   %System%\drivers\dcdavvx.sys (40896 bytes)
   %System%\zpu.dll (53248 bytes)
   %System%\djpssp.bat (120 bytes)

5. Clean the Temporary Internet Files folder, which may contain infected files (How to clean Temporary Internet Files folder).
   
6. Reboot the computer.
   

*Manual removal may cause unexpected system behaviour and should be performed at your own risk.

Static Analysis

VersionInfo

Company Name:
Product Name:
Product Version: 1, 0, 0, 0
Legal Copyright: Copyright 2010
Legal Trademarks:
Original Filename:
Internal Name:
File Version: 1, 0, 0, 0
File Description:
Comments:
Language: English (United States)

Company Name: Product Name: Product Version: 1, 0, 0, 0Legal Copyright: Copyright 2010Legal Trademarks: Original Filename: Internal Name: File Version: 1, 0, 0, 0File Description: Comments: Language: English (United States)

PE Sections

Name	Virtual Address	Virtual Size	Raw Size	Entropy	Section MD5
UPX0	4096	40960	0	0	d41d8cd98f00b204e9800998ecf8427e
UPX1	45056	86016	86016	5.37713	ac06ab7384d890742201d14316140245
.rsrc	131072	4096	2560	2.58534	591af8e314f28dbed7454d42db7c7712

Dropped from:

Downloaded by:

Similar by SSDeep:

Similar by Lavasoft Polymorphic Checker:

Network Activity

URLs

URL	IP
hxxp://www.ppzy.com/start.php?id=13	111.68.2.102

IDS verdicts (Suricata alerts: Emerging Threats ET ruleset)

Traffic

GET /start.php?id=13 HTTP/1.1

Host: 111.68.2.102

Cache-Control: no-cache

HTTP/1.1 404 Not Found

Date: Sat, 08 Mar 2014 20:49:34 GMT

Server: Apache

Content-Length: 207

Connection: close

Content-Type: text/html; charset=iso-8859-1

<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">.<html><head>.<title>404 Not Found</title>.</head><body>.<h1>Not Found</h1>.<p>The requested URL /start.php was not found on this server.</p>.</body></html>...

Map

Strings from Dumps