RANSOM_CERBER.SMJAL

 Analysis by: Michael Jay Villanueva

 ALIASES:

Ransom:Win32/Cerber (Microsoft); Ransom.Cerber (Malwarebytes); Trojan-Ransom.Win32.Zerber.cppa (Kaspersky)

 PLATFORM:

Windows

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Ransomware

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW


This Ransomware arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It deletes the initially executed copy of itself. It is capable of encrypting files in the affected system.

  TECHNICAL DETAILS

File Size:

480,715 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

10 Mar 2017

Arrival Details

This Ransomware arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Ransomware drops the following files:

  • %User Temp%\tmp{random characters}.bmp
  • {folders containing encrypted files}\_HELP_HELP_HELP_{random characters}_.hta
  • {folders containing encrypted files}\_HELP_HELP_HELP_{random characters}_.png
  • %Desktop%\_HELP_HELP_HELP_{random characters}_.hta
  • %Desktop%\_HELP_HELP_HELP_{random characters}_.png
  • %User Temp%\{8 random characters}\{4 random characters}.tmp
  • %User Temp%\{8 random characters}\{4 random characters}.tmp

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %Desktop% is the desktop folder, where it usually is C:\Documents and Settings\{user name}\Desktop in Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\Desktop in Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It creates the following folders:

  • %User Temp%\{8 random characters}

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

Other System Modifications

This Ransomware changes the desktop wallpaper by modifying the following registry entries:

HKEY_CURRENT_USER\Control Panel\Desktop
Wallpaper = %User Temp%\tmp{random characters}.bmp

(Note: The default value data of the said registry entry is {User defined}.)

Other Details

This Ransomware renames encrypted files using the following names:

  • {10 random characters}.{4 random characters}

It deletes the initially executed copy of itself

It is capable of encrypting files in the affected system.

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

13.346.08

FIRST VSAPI PATTERN DATE:

17 Apr 2017

VSAPI OPR PATTERN File:

13.347.00

VSAPI OPR PATTERN Date:

18 Apr 2017

NOTES:

Trend customers:

    Keep your pattern and scan engine files updated. Trend Micro antivirus software can clean or remove most types of computer threats. Malware, though, such as Trojans, scripts, overwriting viruses and joke programs which are identified as uncleanable, should simply be deleted.

All Internet users:

  • Use HouseCall - the Trend Micro online threat scanner to check for malware that may already be on your PC.
  • Catch malware/grayware before they affect your PC or network. Secure your Web world with Trend Micro products that offer the best anti-threat and content security solutions for home users, corporate users, and ISPs. Go here for more information on Trend Micro products that fit your needs.


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