Worm.Win32.Dorkbot_acc13d4e4f
Gen:Variant.Symmi.23548 (BitDefender), Worm:Win32/Dorkbot.I (Microsoft), HEUR:Trojan.Win32.Generic (Kaspersky), Trojan.Win32.Zbot.fdm (v) (VIPRE), Trojan.Packed.24355 (DrWeb), Gen:Variant.Symmi.23548 (B) (Emsisoft), PWS-Zbot-FBDR!ACC13D4E4FFA (McAfee), W32.Virut.CF (Symantec), Worm.Win32.Dorkbot (Ikarus), Gen:Variant.Symmi.23548 (FSecure), BackDoor.Generic17.MHT (AVG), Win32:Virut-ANS (Avast), Possible_DORKBOT (TrendMicro), 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, Packed, 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: acc13d4e4ffa02ce9da144b5374fc522
SHA1: e12288654902248441bdfda2353b0b7a0afacdbc
SHA256: 0d1f0c7a277ab603a9a5eac115db39bb1c57eef9ef04734826f9bed18092f39e
SSDeep: 3072:twX6yB0YfnMqh88W RhjLRHzAA5/RWbzAlzS4wh1JEgxitBOQPYPfWabz765BnO:tNk0YfJhjVLYR/1Kgjgf076fn
Size: 172800 bytes
File type: EXE
Platform: WIN32
Entropy: Packed
PEID: BorlandDelphi30, UPolyXv05_v6
Company: no certificate found
Created at: 2001-12-30 15:14:26
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:1464
%original file name%.exe:1260
The Worm injects its code into the following process(es):
mspaint.exe:660
File activity
The process %original file name%.exe:1464 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%\Application Data\temp.bin (673 bytes)
The process mspaint.exe:660 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)
The Worm deletes the following file(s):
C:\%original file name%.exe (0 bytes)
Registry activity
The process %original file name%.exe:1464 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 1B 00 00 00 01 00 00 00 00 00 00 00"
[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "B7 65 63 AE 29 F9 34 62 27 4F 4A 04 CE 53 4E 8F"
[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"
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"
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 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:1260 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:
[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "05 68 26 C1 5B D1 45 40 95 49 A1 21 D7 C4 73 9D"
[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"
The process mspaint.exe:660 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 1C 00 00 00 01 00 00 00 00 00 00 00"
[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "9F A7 96 14 18 E0 1C CC B1 BB 84 BB BE E0 65 C8"
[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"
Network activity (URLs)
| URL | IP |
|---|---|
| hxxp://api.wipmania.com/ (ET POLICY External IP Lookup Attempt To Wipmania ) |  69.197.137.58 |
| j.lartanat2.com |  Unresolvable |
| j.joyyv02.com | Unresolvable |
| j.balkr02.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:1464
%original file name%.exe:1260 - Delete the original Worm file.
- Delete or disinfect the following files created/modified by the Worm:
%Documents and Settings%\%current user%\Application Data\ScreenSaverPro.scr (673 bytes)
%Documents and Settings%\%current user%\Application Data\temp.bin (673 bytes)
%Documents and Settings%\%current user%\Application Data\Microsoft\Nukmkz.exe (673 bytes) - Delete the following value(s) in the autorun key (How to Work with System Registry):
[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"Screen Saver Pro 3.1" = "%Documents and Settings%\%current user%\Application Data\ScreenSaverPro.scr"
[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"Nukmkz" = "%Documents and Settings%\%current user%\Application Data\Microsoft\Nukmkz.exe" - 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.
