Worm.Win32.Dorkbot_100575b8d0
HEUR:Trojan.Win32.Generic (Kaspersky), Trojan.Win32.Injector.smn (v) (VIPRE), WormDorkbot.YR, GenericUDPFlooder.YR, GenericIRCBot.YR, GenericMSNWorm.YR, GenericUSBInfector.YR, GenericDNSBlocker.YR, GenericAutorunWorm.YR, GenericSYNFlooder.YR, GenericInjector.YR, BankerGeneric.YR, GenericProxy.YR, GenericPhysicalDrive0.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.
MD5: 100575b8d096ec1cbaf16b46cd5c9ffa
SHA1: aa976d1204d042b9ba582fac659d3b3f49f0e60f
SHA256: ab241f8468893c901efb0057b3c138c8b60216c7f166221c374ddb96f09b815a
SSDeep: 3072:f35if jskj la75P10F5lQ5Qz8hNi4yaGCERgzvOK:RiGbwa75Pq5KQzkNfJP6K
Size: 188928 bytes
File type: EXE
Platform: WIN32
Entropy: Not Packed
PEID: UPolyXv05_v6
Company: no certificate found
Created at: 1997-02-08 09:06:27
Analyzed on: WindowsXP SP3 32-bit
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):
%original file name%.exe:752
%original file name%.exe:1240
%original file name%.exe:1376
The Worm injects its code into the following process(es):
ntvdm.exe:992
mspaint.exe:1072
File activity
The process ntvdm.exe:992 makes changes in the file system.
The Worm creates and/or writes to the following file(s):
%WinDir% (672 bytes)
%WinDir%\Temp\Perflib_Perfdata_7a0.dat (4 bytes)
%Documents and Settings%\%current user% (4 bytes)
%Documents and Settings%\%current user%\Local Settings\History\History.IE5\index.dat (4 bytes)
%Documents and Settings%\%current user%\Application Data\Microsoft (4 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\test.pml (6336 bytes)
%Documents and Settings%\%current user%\Application Data (4 bytes)
%System%\config (4 bytes)
C:\$Directory (8 bytes)
%WinDir%\Temp\scs3.tmp (10145 bytes)
%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\index.dat (4 bytes)
%WinDir%\Temp\scs2.tmp (33880 bytes)
%System% (1904 bytes)
The Worm deletes the following file(s):
%WinDir%\Temp\scs2.tmp (0 bytes)
%WinDir%\Temp\scs3.tmp (0 bytes)
The process mspaint.exe:1072 makes changes in the file system.
The Worm creates and/or writes to the following file(s):
%Documents and Settings%\%current user%\Application Data\Microsoft\Nukmkz.exe (673 bytes)
%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\desktop.ini (67 bytes)
%Documents and Settings%\%current user%\Application Data\1.exe (1 bytes)
The Worm deletes the following file(s):
C:\%original file name%.exe (0 bytes)
%Documents and Settings%\%current user%\Application Data\1.tmp (0 bytes)
The process %original file name%.exe:752 makes changes in the file system.
The Worm creates and/or writes to the following file(s):
%Documents and Settings%\%current user%\Application Data\ScreenSaverPro.scr (673 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\chk_fhueioulalaasso (9 bytes)
%Documents and Settings%\%current user%\Application Data\temp.bin (673 bytes)
Registry activity
The process ntvdm.exe:992 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:
[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "4B A5 6E BD A1 6B 17 79 BB E2 E5 9F 2C E1 97 DE"
The process mspaint.exe:1072 makes changes in the system registry.
The Worm 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" = "65452"
"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" = "65452"
[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"
"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"
[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" = "65452"
[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Connections]
"SavedLegacySettings" = "3C 00 00 00 16 00 00 00 01 00 00 00 00 00 00 00"
[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "4E AE 32 07 29 C5 BF 1B 69 A8 DC AB 5E 00 77 E6"
[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" = "65452"
[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"
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]
"Nukmkz" = "%Documents and Settings%\%current user%\Application Data\Microsoft\Nukmkz.exe"
The Worm 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 Worm modifies IE settings for security zones to map all web-nodes that bypassing proxy to the Intranet Zone:
"ProxyBypass" = "1"
Proxy settings are disabled:
[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"
The Worm 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 Worm deletes the following value(s) in system registry:
[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"AutoConfigURL"
"ProxyServer"
"ProxyOverride"
The process %original file name%.exe:752 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:
[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "BC 31 47 A4 0E 29 B8 43 22 60 EC 47 3C 51 01 64"
[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]
"Screen Saver Pro 3.1" = "%Documents and Settings%\%current user%\Application Data\ScreenSaverPro.scr"
The process %original file name%.exe:1240 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:
[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "36 37 66 97 80 B4 F7 F5 F3 42 39 25 56 DF 86 84"
[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"
The process %original file name%.exe:1376 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:
[HKLM\SOFTWARE\Microsoft\DirectDraw\MostRecentApplication]
"ID" = "855385587"
"Name" = "%original file name%.exe"
Network activity (URLs)
| URL | IP |
|---|---|
| hxxp://api.wipmania.com/ (ET POLICY External IP Lookup Attempt To Wipmania ) |  69.197.137.58 |
| a.b444400.com |  183.60.143.34 |
| a.a444400.com |  Unresolvable |
HOSTS file anomalies
No changes have been detected.
Rootkit activity
The Worm installs the following user-mode hooks in WININET.dll:
HttpSendRequestW
InternetWriteFile
HttpSendRequestA
The Worm installs the following user-mode hooks in dnsapi.dll:
DnsQuery_A
DnsQuery_W
The Worm installs the following user-mode hooks in WS2_32.dll:
send
GetAddrInfoW
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
NtQueryDirectoryFile
NtEnumerateValueKey
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
- Click (here) to download and install Ad-Aware Free Antivirus.
- Update the definition files.
- Run a full scan of your computer.
Manual removal*
- Scan a system with an anti-rootkit tool.
- Terminate malicious process(es) (How to End a Process With the Task Manager):
%original file name%.exe:752
%original file name%.exe:1240
%original file name%.exe:1376 - Delete the original Worm file.
- Delete or disinfect the following files created/modified by the Worm:
%WinDir% (672 bytes)
%WinDir%\Temp\Perflib_Perfdata_7a0.dat (4 bytes)
%Documents and Settings%\%current user% (4 bytes)
%Documents and Settings%\%current user%\Local Settings\History\History.IE5\index.dat (4 bytes)
%Documents and Settings%\%current user%\Application Data\Microsoft (4 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\test.pml (6336 bytes)
%System%\config (4 bytes)
C:\$Directory (8 bytes)
%WinDir%\Temp\scs3.tmp (10145 bytes)
%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\index.dat (4 bytes)
%WinDir%\Temp\scs2.tmp (33880 bytes)
%Documents and Settings%\%current user%\Application Data\Microsoft\Nukmkz.exe (673 bytes)
%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\desktop.ini (67 bytes)
%Documents and Settings%\%current user%\Application Data\1.exe (1 bytes)
%Documents and Settings%\%current user%\Application Data\ScreenSaverPro.scr (673 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\chk_fhueioulalaasso (9 bytes)
%Documents and Settings%\%current user%\Application Data\temp.bin (673 bytes) - Delete the following value(s) in the autorun key (How to Work with System Registry):
[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"Nukmkz" = "%Documents and Settings%\%current user%\Application Data\Microsoft\Nukmkz.exe"
[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"Screen Saver Pro 3.1" = "%Documents and Settings%\%current user%\Application Data\ScreenSaverPro.scr" - Clean the Temporary Internet Files folder, which may contain infected files (How to clean Temporary Internet Files folder).
- Find and delete all copies of the worm's file together with "autorun.inf" scripts on removable drives.
- Reboot the computer.
*Manual removal may cause unexpected system behaviour and should be performed at your own risk.
