Threat Description

Backdoor: W32/Hupigon

Details

Category: Malware
Type: Backdoor
Platform: W32
Aliases: Backdoor:W32/Hupigon

Summary


A remote administration utility which bypasses normal security mechanisms to secretly control a program, computer or network.



Removal


Automatic action

Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.

More scanning & removal options

More information on scanning or removal options is available in the documentation for your F-Secure security product on the Downloads section of our Home - Global site.

You may also refer to the Knowledge Base on the F-Secure Community site for more information.

Contact Support

For further assistance, F-Secure customers can request support online via the Request support or the Chat forms on our Home - Global site.



Technical Details


Hupigon variants are backdoor programs, which provide an attacker with access to, and control of, an infected machine. There are a large number of variants in the Hupigon family.

The backdoor's file is a PE executable. The file may be packed with UPX. Unpacked, the code size is 710kB. It is very rare for a Hupigon variant to be smaller than 299kB.

Hupigons are written with Borland Delphi.

The following text strings can typically be found in a Hupigon variant:

  • 6600.org
  • BEI_ZHU
  • GrayPigeon
  • Hacker.com.cn.exe
  • huaihuaitudou
  • Rejoice2007
  • woainisisi
Installation

When the backdoor's file is started, it copies itself as a file named something similar to "Hacker.com.cn.exe" in the Windows System folder and then uses the following processes to make itself to look like a valid Windows program:

  • calc.exe
  • cmd.exe
  • mmc.exe
  • mspaint.exe
  • mstsc.exe
  • notepad.exe
  • osk.exe
  • sndrec.exe
  • sndvol32.exe
  • svchost.exe
  • winchat.exe

It also makes a number of additions to the registry.

Activity

Hupigon variants have several different types of features. The following list is an example of some:

  • It allows others to access the computer
  • Allows for recording with the user's webcam
  • Can make the user's computer to attack various servers
  • Send victim's computer messages
  • Has rootkit functionality so it has a stealth component that hides files
  • Create logs from keystrokes, steals passwords, and sends this information to remote servers
Propagation

Hupigon doesn't have any automatic mechanisms to spread itself. It must be sent by its author via e-mail, through a website, or even via Instant Messengers (IM) such as Yahoo, MSN, ICQ, and Skype.

Creating Hupigon Variants

Hupigon variants are created using kit software. The kit is maintained in a very professional fashion with a highly developed User Interface (UI).

The main UI of the kit can be seen below:

Many options can be set. The "Fast Configuration" shown below enable the following options:

  • Service name is rejoice44.exe
  • Installation path is Msinfo…
  • Password is 1234
  • Icon is taken from MS Media Player
  • Uses Internet Explorer to bypass firewall
  • Create mutex and remove installer from installer folder
  • Pack code by using UPX
  • Self/auto-clone protected installation path is "system32"
  • Executable is calc.exe

There is also a "rootkit" option available. Other options including adding a URL to target for a Distributed Denial of Service (DDoS) attack:

The kit as default settings to create mutexes. Many Hupigon variants therefore create mutexes in the following format:

  • xxx.com.cn_MUTEX

The "xxx" being a variable, for example: Hacker.com.cn_MUTEX

Registry Modifications

Creates these keys:

  • HKLM\System\CurrentControlSet\Services\system32 ImagePath = C:\WINDOWS\Hacker.com.cn.exe
  • HKLM\System\CurrentControlSet\Services\system32
  • HKLM\System\CurrentControlSet\Services\system32\Security





SUBMIT A SAMPLE

Suspect a file or URL was wrongly detected? Submit a sample to our Labs for analysis

Submit Now

Give And Get Advice

Give advice. Get advice. Share the knowledge on our free discussion forum.

Learn More