Ransom.Win32.UPPER.A

April 17, 2020
 Analysis by: Mohammed Malubay
 ALIASES:

a variant of Win32/Filecoder.NSF trojan(NOD32); Trojan-Ransom.FileCrypter(IKARUS);

 PLATFORM:

Windows

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

  • Threat Type: Ransomware

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware

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.

It avoids encrypting files with the following file extensions.

  TECHNICAL DETAILS

File Size:

517,632 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

23 Mar 2020

Payload:

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 adds the following processes:

  • %System%\vssadmin.exe delete shadows /all /quiet → deletes shadow copies

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

Process Termination

This Ransomware terminates the following processes if found running in the affected system's memory:

  • ocssd.exe
  • fdlauncher.exe
  • ocautoupds.exe
  • firefoxconfig.exe
  • sqlwriter.exe
  • sqlagent.exe
  • mysqld-nt.exe
  • MsDtsSrvr.exe
  • postgres.exe
  • sqlservr.exe
  • synctime.exe
  • sqlserv.exe
  • Ssms.exe
  • oracle.exe
  • UniFi.exe
  • fdhost.exe
  • mydesctopservice.exe
  • mysqld-opt.exe
  • ocomm.exe
  • tbirdconfig.exe
  • ntdbsmgr.exe
  • sqlceip.exe
  • mysqld.exe
  • dbsnmp.exe
  • msmdsrv.exe
  • sqlbrowser.exe
  • pg_ctl.exe
  • msftesql.exe

Other Details

This Ransomware does the following:

  • It terminates the following services:
    • UniFi
    • MSSQLSERVER
    • SQLSERVERAGENT
    • SQLWriter
    • vmms
    • MSSQL
    • SQLAgent
    • MSSQLFDLauncher
    • SQLBrowser
    • Browser

It deletes itself after execution.

Ransomware Routine

This Ransomware avoids encrypting files with the following strings in their file name:

  • infoUPPER.txt

It avoids encrypting files with the following strings in their file path:

  • AppData

It avoids encrypting files found in the following folders:

  • C:\Windows
  • C:\System Volume Information

It appends the following extension to the file name of the encrypted files:

  • .UPPER

It leaves text files that serve as ransom notes containing the following text:

  • {Encrypted Directory}\infoUPPER.txt

It avoids encrypting files with the following file extensions:

  • .bat
  • .cmd
  • .com
  • .cpl
  • .dll
  • .lnk
  • .ms
  • .msc
  • .msp
  • .pif
  • .scr
  • .sys
  • .UPPER

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

15.810.06

FIRST VSAPI PATTERN DATE:

17 Apr 2020

VSAPI OPR PATTERN File:

15.811.00

VSAPI OPR PATTERN Date:

18 Apr 2020

Step 1

Trend Micro Predictive Machine Learning detects and blocks malware at the first sign of its existence, before it executes on your system. When enabled, your Trend Micro product detects this malware under the following machine learning name:

     Troj.Win32.TRX.XXPE50FFF034

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

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 4

Search and delete these files

[ 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.
  • {Encrypted Directory}\infoUPPER.txt

Step 5

Restore encrypted files from backup.

Step 6

Scan your computer with your Trend Micro product to delete files detected as Ransom.Win32.UPPER.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 the following Trend Micro Support pages for more information:


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