Trojan.Win32.VBKrypt.deqp_fdbad286d6

by malwarelabrobot on October 11th, 2013 in Malware Descriptions.

Trojan.Win32.VBKrypt.deqp (Kaspersky), Virtool.Win32.Vbinject.Gen.2 (v) (VIPRE), Trojan.Win32.VBKrypt!IK (Emsisoft), GenericUSBInfector.YR, GenericUDPFlooder.YR, GenericIRCBot.YR, GenericAutorunWorm.YR, GenericInjector.YR (Lavasoft MAS)
Behaviour: Trojan, Flooder, Worm, WormAutorun, IRCBot, UDPFlooder, 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: fdbad286d6b883629074bd93d5a0d735
SHA1: 30203dbf9a737e3c0f9b88c7be1cc728e2753dc9
SHA256: 335cdda9f9ca929463154ef2126a78e2af1c81c6ece9d3acde43ecffd205a9e2
SSDeep: 12288:tIHgOnjEXVyypkz1jt4ggFULie6ef89dvMbeRsPtsByVXmYjsI9:tBOnjk9AqFzHms0VXmYjV9
Size: 1630208 bytes
File type: EXE
Platform: WIN32
Entropy: Not Packed
PEID: MicrosoftVisualBasicv50v60, UPolyXv05_v6
Company: no certificate found
Created at: 2011-05-27 17:24:02


Summary:

Trojan. A program that appears to do one thing but actually does another (a.k.a. Trojan Horse).

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 Trojan'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.
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.
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 Trojan creates the following process(es):

fdbad286d6b883629074bd93d5a0d735.exe:740
fdbad286d6b883629074bd93d5a0d735.exe:632
Lskmkx.exe:1072
Lskmkx.exe:376

File activity

The process fdbad286d6b883629074bd93d5a0d735.exe:740 makes changes in a file system.
The Trojan creates and/or writes to the following file(s):

%Documents and Settings%\%current user%\Application Data\Lskmkx.exe (10177 bytes)

Registry activity

The process fdbad286d6b883629074bd93d5a0d735.exe:740 makes changes in a system registry.
The Trojan creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "64 4F 79 45 84 4D 40 57 5A F8 A4 5C 55 4F E5 DD"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\system]
"Shell" = "explorer.exe,%Documents and Settings%\%current user%\Application Data\Lskmkx.exe"

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

[HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System]
"Shell" = "explorer.exe,%Documents and Settings%\%current user%\Application Data\Lskmkx.exe"

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

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

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
"Lskmkx" = "%Documents and Settings%\%current user%\Application Data\Lskmkx.exe"

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

The process fdbad286d6b883629074bd93d5a0d735.exe:632 makes changes in a system registry.
The Trojan creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "78 B6 99 27 49 DA 1A 71 67 0A 92 41 54 86 BA F3"

The process Lskmkx.exe:1072 makes changes in a system registry.
The Trojan creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "55 13 37 CC 63 68 22 AF 3B FA CA 77 3A D7 57 96"

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

The process Lskmkx.exe:376 makes changes in a system registry.
The Trojan creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "46 06 AB 82 6D 17 5A E2 83 7E 26 BC 30 57 58 99"

Network activity (URLs)

No activity has been detected.

Rootkit activity

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

HttpSendRequestW
InternetWriteFile
HttpSendRequestA

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

send

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

MoveFileA
CopyFileW
CopyFileA
MoveFileW
CreateFileW
CreateFileA

The Trojan 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 Trojan'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.


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):

    fdbad286d6b883629074bd93d5a0d735.exe:740
    fdbad286d6b883629074bd93d5a0d735.exe:632
    Lskmkx.exe:1072
    Lskmkx.exe:376

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

    %Documents and Settings%\%current user%\Application Data\Lskmkx.exe (10177 bytes)

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

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

    [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
    "Lskmkx" = "%Documents and Settings%\%current user%\Application Data\Lskmkx.exe"

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