arrow_back
search
close

RANSOM_XDATA.A

June 20, 2017
 ALIASES:

Trojan.Ransom.Xdata(ALYac)

 PLATFORM:

Windows

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

  • Threat Type: Ransomware

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Dropped by other malware, Downloaded from the Internet

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 itself after execution.

  TECHNICAL DETAILS

File Size:

944,128 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

19 May 2017

Payload:

Encrypts files, Displays message/message boxes

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:

  • %Application Data%\{file name}
    where {file name} can be any of the following:
    • mssql.exe
    • mscomrpc.exe
    • mscom.exe
    • msdcom.exe
    • mssec.exe
    • mssecsvc.exe
    • msdns.exe
    • msaddc.exe
  • %Application Data%\{file name} - copy of itself
    where {file name} can be any of the following:
    • lsm.exe
    • conhost.exe
    • dwm.exe
    • smss.exe
    • lsass.exe
    • wuaclt.exe
    • services.exe
    • svchost.exe
    • taskhost.exe
    • wininit.exe
  • %All Users Profile%\{computer name}#-{random values}-#-{yyyyMMddhhmmss}-{random number}.key
  • %System Root%\{computer name}#-{random values}-#-{yyyyMMddhhmmss}-{random number}.key
  • %Desktop%\{computer name}#-{random values}-#-{yyyyMMddhhmmss}-{random number}.key
  • %Application Data%\{file name}
    where {file name} can be any of the following:
    • explorer.exe
    • spoolss.exe
    • spoolsv.exe
    • system.exe
  • {folder of encrypted files}\HOW_CAN_I_DECRYPT_MY_FILES.txt - ransom note

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming 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.. %All Users Profile% is the All Users folder, where it usually is C:\Documents and Settings\All Users on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\ProgramData 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.. %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %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.)

Other Details

This Ransomware does the following:

  • It clears all Windows Event logs using the wevtutil.exe command.

It deletes itself after execution.

Ransomware Routine

This Ransomware renames encrypted files using the following names:

  • {original filename and extension}.~xdata~

NOTES:

The ransom note contains the following:

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

13.416.05

FIRST VSAPI PATTERN DATE:

19 May 2017

VSAPI OPR PATTERN File:

13.417.00

VSAPI OPR PATTERN Date:

20 May 2017

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 3

Restart in Safe Mode

[ Learn More ]

Step 4

Search and delete this file

[ Learn More ]
There may be some files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.  
  • {folder of encrypted files}\HOW_CAN_I_DECRYPT_MY_FILES.txt
  • explorer.exe
  • spoolss.exe
  • spoolsv.exe
  • system.exe
  • mssql.exe
  • mscomrpc.exe
  • mscom.exe
  • msdcom.exe
  • mssec.exe
  • mssecsvc.exe
  • msdns.exe
  • msaddc.exe
  • %All Users Profile%\{computer name}#-{random values}-#-{yyyyMMddhhmmss}-{random number}.key
  • %System Root%\{computer name}#-{random values}-#-{yyyyMMddhhmmss}-{random number}.key
  • %Desktop%\{computer name}#-{random values}-#-{yyyyMMddhhmmss}-{random number}.key

Step 5

Restart in normal mode and scan your computer with your Trend Micro product for files detected as RANSOM_XDATA.A. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.

Step 6

Restore encrypted files from backup.


Did this description help? Tell us how we did.