Worm.Win32.Dorkbot_c1c05527b0

by malwarelabrobot on October 18th, 2013 in Malware Descriptions.

HEUR:Trojan.Win32.Generic (Kaspersky), Trojan.Win32.Encpk.pa (v) (VIPRE), Trojan.Win32.Buzus!IK (Emsisoft), GenericUSBInfector.YR, GenericProxy.YR, GenericSYNFlooder.YR, GenericUDPFlooder.YR, GenericDNSBlocker.YR, GenericMSNWorm.YR, GenericIRCBot.YR, GenericAutorunWorm.YR, WormDorkbot.YR, GenericPhysicalDrive0.YR, GenericInjector.YR, BankerGeneric.YR (Lavasoft MAS)
Behaviour: Banker, Trojan, Flooder, Worm, WormAutorun, IRCBot, MSNWorm, DNSBlocker, UDPFlooder, SYNFlooder, Trojan-Proxy, USBInfector


The description has been automatically generated by Lavasoft Malware Analysis System and it may contain incomplete or inaccurate information.

Summary
Technical Details
Removal Recommendations

MD5: c1c05527b0ab6f2f8d90c5fad3401edd
SHA1: 1646597c96b205852dc8c6a1f2fd16d5d66fd729
SHA256: baaf153ddd0a1239619ff2fb5640901f5fb369b483b00ea7d8083265d5bf9558
SSDeep: 6144:JqBEMAxXo8wCy6fujTinjW8r/U8ieUr2LDn:ABEBPHujl8BUq
Size: 237568 bytes
File type: EXE
Platform: WIN32
Entropy: Not Packed
PEID: Armadillov171, MicrosoftVisualC, MicrosoftVisualCv50v60MFC, MicrosoftVisualC50, UPolyXv05_v6
Company: no certificate found
Created at: 2011-08-28 15:50:07


Summary:

Worm. A program that is primarily replicating on networks or removable drives.

Payload

Behaviour Description
WormAutorun A worm can spread via removable drives. It writes its executable and creates "autorun.inf" scripts on all removable drives. The autorun script will execute the Worm's file once a user opens a drive's folder in Windows Explorer.
IRCBot A bot can communicate with command and control servers via IRC channel.
MSNWorm A worm can spread its copies through the MSN Messanger.
DNSBlocker A program can block designated DNS servers for making it difficult for users to locate specific domains or web sites on the Internet.
UDPFlooder This program can make a UDP flood. A UDP flood attack is a denial-of-service attack using the User Datagram Protocol (UDP). It can be initiated by sending a large number of UDP packets to random ports on a remote host.
SYNFlooder This program can make a SYN flood. It is a form of denial-of-service attack in which an attacker sends a succession of SYN requests to a target's system in an attempt to consume enough server resources to make the system unresponsive to legitimate traffic.
Trojan-Proxy This program can launch a proxy server (SOCKS4) on a designated TCP port.
USBInfector A program can register a device notification with the help of RegisterDeviceNotification. So it is notified when a USB device is plugged and then the worm copies itself to the USB device plugged into the affected computer.


Process activity

The Worm creates the following process(es):

Gpwiwo.exe:2856
Gpwiwo.exe:2812
c1c05527b0ab6f2f8d90c5fad3401edd.exe:268

The Worm injects its code into the following process(es):

ctfmon.exe:252

File activity

The process c1c05527b0ab6f2f8d90c5fad3401edd.exe:268 makes changes in a file system.
The Worm creates and/or writes to the following file(s):

%Documents and Settings%\%current user%\Application Data\Gpwiwo.exe (1281 bytes)

Registry activity

The process ctfmon.exe:252 makes changes in a system registry.
The Worm deletes the following value(s) in system registry:
The Worm disables automatic startup of the application by deleting the following autorun value:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"internat.exe"

The process Gpwiwo.exe:2856 makes changes in a system registry.
The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "36 25 A8 39 C8 1C 72 3B 2D C5 31 20 D2 2B 92 90"

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

The process Gpwiwo.exe:2812 makes changes in a system registry.
The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "49 03 FD 1D 7F B6 3E DD E8 5F C2 AC 78 E7 55 0B"

The process c1c05527b0ab6f2f8d90c5fad3401edd.exe:268 makes changes in a system registry.
The Worm creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "BE 46 42 6A E1 88 A2 99 A8 5D 0F 1E A2 0C 05 6E"

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

To automatically run itself each time Windows is booted, the Worm adds the following link to its file to the system registry autorun key:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"Gpwiwo" = "%Documents and Settings%\%current user%\Application Data\Gpwiwo.exe"

Network activity (URLs)

No activity has been detected.

Rootkit activity

The Worm installs the following user-mode hooks in urlmon.dll:

URLDownloadToFileA
URLDownloadToFileW

The Worm installs the following user-mode hooks in WININET.dll:

InternetWriteFile
HttpSendRequestA
HttpSendRequestW

The Worm installs the following user-mode hooks in ADVAPI32.dll:

RegCreateKeyExA
RegCreateKeyExW

The Worm installs the following user-mode hooks in WS2_32.dll:

send
getaddrinfo

The Worm installs the following user-mode hooks in kernel32.dll:

MoveFileA
CopyFileW
CopyFileA
MoveFileW
CreateFileW
CreateFileA

The Worm installs the following user-mode hooks in ntdll.dll:

LdrLoadDll
NtResumeThread
ZwQueryDirectoryFile
ZwEnumerateValueKey

Propagation

A worm can spread via removable drives. It writes its executable and creates "autorun.inf" scripts on all removable drives. The autorun script will execute the Worm's file once a user opens a drive's folder in Windows Explorer.
A program can register a device notification with the help of RegisterDeviceNotification. So it is notified when a USB device is plugged and then the worm copies itself to the USB device plugged into the affected computer.
A worm can spread its copies through the MSN Messanger.


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):

    Gpwiwo.exe:2856
    Gpwiwo.exe:2812
    c1c05527b0ab6f2f8d90c5fad3401edd.exe:268

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

    %Documents and Settings%\%current user%\Application Data\Gpwiwo.exe (1281 bytes)

  5. Delete the following value(s) in the autorun key (How to Work with System Registry):

    [HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
    "Gpwiwo" = "%Documents and Settings%\%current user%\Application Data\Gpwiwo.exe"

  6. Find and delete all copies of the worm's file together with "autorun.inf" scripts on removable drives.
  7. Reboot the computer.

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