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Ransom:Win32/Reveton

First posted on 18 June 2019.
Source: Microsoft

Aliases :

Ransom:Win32/Reveton is also known as FBI moneypak, Lockscreen, FBI virus.

Explanation :

Installation

When run, some variants of Ransom:Win32/Reveton copy themselves to your PC using the following naming scheme:

%ALLUSERPROFILE%Application Data.

For example, if the original file name is malware.dll, the copy's name is erawlam.lld.

Other variants copy themselves to the above location using random file names with the extension .plz or .dat, for example %ALLUSERPROFILE%Application Data6j1fqm4L.plz.

Certain variants make the following changes to the registry so that the threat runs each time you start your PC:

In subkey: HKCUSoftwareMicrosoftWindowsCurrentVersionRun
Sets value: "Task Scheduler"
With data: "%ALLUSERPROFILE%Application Data ask scheduler ask scheduler.exe"

In subkey: HKLMSystemControlSet001servicesWinmgmtParameters
Sets value: "ServiceDll"
With data: "%ALLUSERPROFILE%Application Data.plz"

These registry entries might be created by a registry file that Reveton drops onto your PC in the %ALLUSERPROFILE%Application Datafolder using a file name that is usually the same as the copied component, but with a .reg extension, for example:

%ALLUSERPROFILE%Application Data6j1fqm4l.reg

This file might be detected as a Ransom:WinREG/Reveton variant, like Ransom:WinREG/Reveton.B.

Some Reveton variants might also add their dropped copy to the Data Execution Prevention (DEP) exception list, which lets it to bypass checks in Windows so that it can run, by making the following registry modification:

In subkey: HKLMSOFTWAREMicrosoftWindows NTCurrentVersionAppCompatFlagsLayers
Sets value: "%ALLUSERPROFILE%Application Data ask schedulerTask Scheduler.exe"
With data: "disablenxshowui"

Some variants of Ransom:Win32/Reveton create the following shortcut file in the Windows to ensure the threat loads every time you log on; this threat has used the following names:

ctfmon.lnk task scheduler.lnk runctf.lnk regmonstd.lnk

Variants like Ransom:Win32/Reveton.X create the shortcut using a random file name consistent of letters and digits, for example jw2gf7j6.lnk. This file is detected as Ransom:Win32/Reveton!lnk.

Manually clicking the shortcut will also run the threat.

Some Ransom:Win32/Reveton variants might also drop a copy of rundll32.exe in the %USERPROFILE%application data folder with the file name lsass.exe. This file is then used to launch the threat, for example:

lsass.exe .dll, GOF1

Other variants, like Ransom:Win32/Reveton.X, launch the threat using the original rundll32.exe file located in your PC's .

In some older variants of Ransom:Win32/Reveton, the threat creates a shortcut file with the file name .dll.lnk.

Distribution

Typically, Ransom:Win32/Reveton is installed on a PC as a result of a drive-by download attack, for example, by an exploit pack, or you might encounter it if you visit a hacked page.

We have observed, for instance, other malware, like Exploit:Win32/Pdfjsc.ADY and Exploit:Win32/Pdfjsc.ADQ, which can be distributed via the Blacoleexploit pack, download Ransom:Win32/Reveton onto hacked PCs.

Payload

Prevents you from using your PC

As part of its payload, Ransom:Win32/Reveton displays a full-screen webpage that covers all other windows, rendering your PC unusable. The image is a fake warning pretending to be from a legitimate institution which demands the payment of a fine.

Paying the "fine" will not necessarily return your PC to a usable state.

Some examples of localized images that variants of Ransom:Win32/Reveton might display are reproduced here.

An image pretending to be from the USDepartment of Homeland Security:

An image pretending to be from the Department of Justice, USA:

An image pretending to be from New Scotland Yard, Metropolitan Police and Strathclyde Police:

An image pretending to be from the Bundespolizei, or German Federal Police, National Cyber Crimes Unit:

Images pretending to be from the Federal Bureau of Investigation, or FBI:

An image pretending to be from the PC Crime & Intellectual Property Section of the United States Department of Justice:

An image pretending to be from the Cuerpro Nacional De Policia, or National Police Corps of Spain:

An image pretending to be from the Guardia di Finanza, or Italian Financial Guard:

Downloads and runs other malware components

Ransom:Win32/Reveton can download and run customized DLL payloads, like the following:

Lock.dll , which the threat injects into browser process, including the following, to display the fraudulent message: chrome.exe firefox.exe iexplore.exe opera.exe FileMem.dll , which is an encrypted file that might do different payloads, including information-stealing routines, and might be detected as PWS:Win32/Reveton

Reveton can also download a DLL file that it stores in a container file with a random name and a .pad or .pff extension, for example e8al.pad androdolcdod.pff.

It puts this file in the %ALLUSERPROFILE%Application Data or %TEMP% folders. This DLL is used to display the lock screen message and might be detected as Ransom:Win32/Reveton.U or Ransom:Win32/Reveton.V.

It might load these files into memory, rather than downloading them to a specific location on your PC.

In the wild, we have observed variants of Ransom:Win32/Reveton downloading these DLL files, images, and other bundled malware from the following IP addresses, using port 80 or 443:

146.185.218.52 146.185.255.194 195.191.56.194 195.208.185.33 213.152.172.101 58.107.26.174 82.192.88.13 85.143.166.132 85.143.166.136 whatwillber.com willber.com

Changes Internet browser settings

Some variants of Ransom:Win32/Reveton might change Internet Explorer settings by making a number of registry changes.

Disable Internet Explorer security warnings:

In subkey: HKCUSoftwareMicrosoftInternet ExplorerMain
Sets value: "NoProtectedModeBanner"
With data: "1"

Lock the Internet Explorer toolbar:

In subkey: HKCUSoftwareMicrosoftInternet ExplorerToolbar
Sets value: "Locked"
With data: "1"

Lower Internet zone security settings:

In subkey: HKCUSoftwareMicrosoftWindowsCurrentVersionInternet Settingsones
Sets value: "1609"
With data: "0"

In subkey: HKCUSoftwareMicrosoftWindowsCurrentVersionInternet Settingsones1
Sets value: "1609"
With data: "0"

In subkey: HKCUSoftwareMicrosoftWindowsCurrentVersionInternet Settingsones2
Sets value: "1609"
With data: "0"

In subkey: HKCUSoftwareMicrosoftWindowsCurrentVersionInternet Settingsones3
Sets value: "1609"
With data: "0"

In subkey: HKCUSoftwareMicrosoftWindowsCurrentVersionInternet Settingsones4
Sets value: "1609"
With data: "0"

Changes PC settings

Some variants might disable Task Manager by making the following registry change:

In subkey: HKCUSoftwareMicrosoftWindowsCurrentVersionPoliciesSystem
Sets value: "DisableTaskMgr"
With data: "1"

Some Reveton variants can also hide icons from appearing on your desktop by making the following registry change:

In subkey: HKCUSoftwareMicrosoftWindowsCurrentVersionExplorerAdvanced
Sets value: "HideIcons"
With data: "1"

Ends processes

To prevent you from ending the malware process, some variants of Ransom:Win32/Reveton might end the process taskmgr.exe as soon as it is run.

Additional information

The origin of the name Reveton was taken from the first variant (Ransom:Win32/Reveton.A) that contains the string "NOTEVER". It is the reversed string for "REVETON".

We have observed Ransom:Win32/Reveton using a variety of legitimate payment and financial transfer services, including the following:

Green Dot MoneyPak Paysafecard Ukash Ultimate Game Card

These providers are not affiliated with Ransom:Win32/Reveton.

If you believe you are a victim of fraud involving one of these services, you should contact them, along with your local authorities.

Related encyclopedia entries

Ransom:Win32/Reveton!lnk

PWS:Win32/Reveton

Analysis by Amir Fouda and Edgardo Diaz

Last update 18 June 2019

 

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