Worm.Win32.Dorkbot_53b971db14
Trojan-Dropper.Win32.WormDrop.di (Kaspersky), Trojan.Win32.Generic.pak!cobra (VIPRE), Worm.Win32.Dorkbot!IK (Emsisoft), 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: Trojan-Dropper, 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: 53b971db14a790a6457a18148a470fba
SHA1: 683cd9111c473c10179cfa880a7f67e807381a13
SHA256: 391cdbbc7c64f5b0cb9de1eb5d1f4edc7b786089954945e2fff53006b70372f6
SSDeep: 3072:cceId2Z0p2H1BFSHxFc6CiBd9jkHIRwhz:ccFdDpkDSRFcHiBd9jkHw
Size: 140800 bytes
File type: EXE
Platform: WIN32
Entropy: Packed
PEID: MicrosoftVisualC, MicrosoftVisualCv50v60MFC, MicrosoftVisualC50, UPolyXv05_v6, Armadillov171
Company: no certificate found
Created at: 2015-05-10 21:11:38
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:1508
Yukmkk.exe:580
The Worm injects its code into the following process(es):
No processes have been created.
File activity
The process %original file name%.exe:1508 makes changes in the file system.
The Worm creates and/or writes to the following file(s):
%Documents and Settings%\%current user%\Application Data\Yukmkk.exe (673 bytes)
Registry activity
The process %original file name%.exe:1508 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:
[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "77 5B F9 AB 84 79 B7 47 F5 5C F7 25 6A E8 E3 E8"
[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]
"Yukmkk" = "%Documents and Settings%\%current user%\Application Data\Yukmkk.exe"
The process Yukmkk.exe:580 makes changes in the system registry.
The Worm creates and/or sets the following values in system registry:
[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "7D 6B A0 F5 C3 22 0B 63 F7 15 82 5F C3 04 16 E4"
[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"
Network activity (URLs)
| URL | IP |
|---|---|
| hxxp://api.wipmania.com/ (ET POLICY External IP Lookup Attempt To Wipmania ) |  69.197.137.58 |
| av.shannen.cc |  89.248.171.57 |
| up.scorevidic.net |  Unresolvable |
| av.psybnc.cz | 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 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
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:1508
Yukmkk.exe:580 - Delete the original Worm file.
- Delete or disinfect the following files created/modified by the Worm:
%Documents and Settings%\%current user%\Application Data\Yukmkk.exe (673 bytes)
- Delete the following value(s) in the autorun key (How to Work with System Registry):
[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"Yukmkk" = "%Documents and Settings%\%current user%\Application Data\Yukmkk.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.
