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Trojan.Ransomgerpo

Risk Level 1: Very Low

Discovered:
April 3, 2011
Updated:
April 4, 2011 8:12:39 AM
Type:
Trojan
Infection Length:
Varies
Systems Affected:
Windows 2000, Windows 7, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows Server 2008, Windows Vista, Windows XP
When executed, the Trojan creates one of the following registry entries so that it runs every time Windows starts:
  • HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Winlogon\"Shell" = "%CurrentFolder%\[ORIGINAL THREAT FILE NAME].exe"
  • HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Winlogon\"Shell" = "%CurrentFolder%\[ORIGINAL THREAT FILE NAME].exe"

Next, the Trojan creates the following registry entry to alter behavior when certain files are accessed or executed:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\taskmgr.exe\"Debugger" = "calc.exe"

Next, the Trojan may create the following registry entries:
  • HKEY_CURRENT_USER\Software\tetris\"level" = "[BINARY DATA]"
  • HKEY_CURRENT_USER\Software\tetris\"phone" = "[RANDOM CHARACTERS]"

The Trojan then attempts to access following remote site:
[http://]78.26.187.232/[REMOVED]

It ends the following processes:
  • taskmgr.exe
  • explorer.exe

It then locks the desktop and displays a message in German asking the user to pay money by Ukash to unlock the computer.





The message displayed is as follows:
Die offizielle Mitteilung der Bundeskriminalamt

Achtung!

Ein Vorgang illegaler Aktivitaten wurde erkannt.

Das Betriebssystem wurde im Zusammenhang mit Verstossen gegen die Gesetze der Bundesrepublik Deutschland gesperrt! Es wurde folgender Vertoss festegestellt: Ihre IP Adresse lautet "" mit dieser IP wurden Seiten mit pornografischen Inhalten, Kinderpornographie, Sodomie und Gewalt gegen Kinder aufgerufen.

Auf Ihrem Computer wurden ebenfalls Videodateien mit pornografischen Inhalten, Elementen von Gewalt und Kinderpornografie festgestellt!

Es wurden auch Emails in Form von Spam, mit terroristischen Hintergr?nden, verschickt. Diese Sperre des Computers dient dazu, Ihre illegalen Aktivitaten zu unterbinden.


Ihre Daten:

IP:
Browser:
OS:
Das Land:
City:
ISP: Um die Sperre des Computers aufzuheben, sind Sie dazu verflichtet eine Strafe von 100 Euro zu zahlen.

Die Zahlung ist innerhalb von 24 Stunden zu leisten. Sollte der Eingang der Zahlung in der vorgegebenen Zeit nicht erfolgen, so wird Ihre Festplatte unwiderruflich formatiert(gel?scht).

Die Bezahlung erfolgt durch einen Ukash Coupon-Code in Hohe von 100 Euro.

Um die Bezahlung durchzufuhren, geben Sie bitte den erworbenen Code in das Zahlungsfeld ein und dr?cken Sie anschliessend auf OK (haben Sie mehrere Codes, so geben Sie Diese einfach nacheinander ein und drucken Sie anschliessend auf OK)

Sollte das System Fehler melden, so m?ssen Sie den Code per Email[REMOVED] versenden.

Nach Eingang der Zahlung wird Ihr Computer innerhalb von 24 Stunden wieder freigestellt.


The ukash coupon number will be sent to following location:
[http://]anamath.cz.cc/[REMOVED]

Recommendations

Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":

  • Use a firewall to block all incoming connections from the Internet to services that should not be publicly available. By default, you should deny all incoming connections and only allow services you explicitly want to offer to the outside world.
  • Enforce a password policy. Complex passwords make it difficult to crack password files on compromised computers. This helps to prevent or limit damage when a computer is compromised.
  • Ensure that programs and users of the computer use the lowest level of privileges necessary to complete a task. When prompted for a root or UAC password, ensure that the program asking for administration-level access is a legitimate application.
  • Disable AutoPlay to prevent the automatic launching of executable files on network and removable drives, and disconnect the drives when not required. If write access is not required, enable read-only mode if the option is available.
  • Turn off file sharing if not needed. If file sharing is required, use ACLs and password protection to limit access. Disable anonymous access to shared folders. Grant access only to user accounts with strong passwords to folders that must be shared.
  • Turn off and remove unnecessary services. By default, many operating systems install auxiliary services that are not critical. These services are avenues of attack. If they are removed, threats have less avenues of attack.
  • If a threat exploits one or more network services, disable, or block access to, those services until a patch is applied.
  • Always keep your patch levels up-to-date, especially on computers that host public services and are accessible through the firewall, such as HTTP, FTP, mail, and DNS services.
  • Configure your email server to block or remove email that contains file attachments that are commonly used to spread threats, such as .vbs, .bat, .exe, .pif and .scr files.
  • Isolate compromised computers quickly to prevent threats from spreading further. Perform a forensic analysis and restore the computers using trusted media.
  • Train employees not to open attachments unless they are expecting them. Also, do not execute software that is downloaded from the Internet unless it has been scanned for viruses. Simply visiting a compromised Web site can cause infection if certain browser vulnerabilities are not patched.
  • If Bluetooth is not required for mobile devices, it should be turned off. If you require its use, ensure that the device's visibility is set to "Hidden" so that it cannot be scanned by other Bluetooth devices. If device pairing must be used, ensure that all devices are set to "Unauthorized", requiring authorization for each connection request. Do not accept applications that are unsigned or sent from unknown sources.
  • For further information on the terms used in this document, please refer to the Security Response glossary.
Writeup By: Kaoru Hayashi
Summary| Technical Details| Removal

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