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Ransom.Win32.PWNDLOCKER.B

April 08, 2020
 Analysis by: Mohammed Malubay
 ALIASES:

W32/Pwnd.B!tr.ransom(FORTINET); a variant of Win32/Filecoder.OAZ trojan(NOD32);

 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


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 avoids encrypting files with the following file extensions.

  TECHNICAL DETAILS

File Size:

17,408 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

09 Mar 2020

Payload:

Displays message/message boxes, Encrypts files

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
  • %System%\vssadmin.exe resize shadowstorage /for={drive letter}: /on={drive letter}: /maxsize=401MB → resizes the maximum amount of storage space that can be used for shadow copy storage
  • %System%\vssadmin.exe resize shadowstorage /for={drive letter}: /on={drive letter}: /maxsize=unbounded → resizes the maximum amount of storage space that can be used for shadow copy storage

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

Other System Modifications

This Ransomware deletes the following files:

  • %All Users Profile%\boxed-join.avi
  • %All Users Profile%\clean.bat

(Note: %All Users Profile% is the common user's profile folder, which is usually C:\Documents and Settings\All Users on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit). )

Process Termination

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

  • Processes that starts with the following strings:
    • agntsv
    • cntaos
    • dbeng5
    • dbsnmp
    • encsvc
    • excel.
    • firefo
    • infopa
    • isqlpl
    • mbamtr
    • msacce
    • msftes
    • mspub.
    • mydesk
    • mysqld
    • ntrtsc
    • ocauto
    • ocomm.
    • ocssd.
    • onenot
    • oracle
    • outloo
    • pccntm
    • powerp
    • sqbcor
    • sqlage
    • sqlbro
    • sqlser
    • sqlwri
    • steam.
    • syncti
    • tbirdc
    • thebat
    • thunde
    • tmlist
    • visio.
    • winwor
    • wordpa
    • xfssvc
    • zoolz

Other Details

This Ransomware does the following:

  • Terminates the following network services:
    • Acronis VSS Provider
    • AcronisAgent
    • Alerter
    • BackupExecAgentAccelerator
    • BackupExecDeviceMediaService
    • BackupExecJobEngine
    • BackupExecManagementService
    • BackupExecRPCService
    • BackupExecVSSProvider
    • BASupportExpressSrvcUpdater_N_Central
    • BASupportExpressStandaloneService_N_Central
    • bbagent
    • CSFalconService
    • DFSR
    • epag
    • EPIntegrationService
    • EPProtectedService
    • epredline
    • EPSecurityService
    • EPUpdateService
    • EqlReqService
    • EqlVss
    • hasplms
    • macmnsvc
    • masvc
    • MB3Service
    • MBAMService
    • MBEndpointAgent
    • McAfeeDLPAgentService
    • McAfeeFramework
    • mfemms
    • mozyprobackup
    • MsDtsServer
    • MSExchangeADTopology
    • MSExchangeDelivery
    • MSExchangeDiagnostics
    • MSExchangeEdgeSync
    • MSExchangeES
    • MSExchangeHM
    • MSExchangeHMRecovery
    • MSExchangeIS
    • MSExchangeMailboxReplication
    • MSExchangeMGMT
    • MSExchangeMTA
    • MSExchangeRepl
    • MSExchangeRPC
    • MSExchangeSA
    • MSExchangeServiceHost
    • MSExchangeSRS
    • MSExchangeTransport
    • MSExchangeUM
    • MSExchangeUMCR
    • MSMQ
    • MSOLAP$*
    • MSOLAP$SQL_2008
    • MSOLAP$SYSTEM_BGC
    • MSOLAP$TPS
    • MSOLAP$TPSAMA
    • MSSQL$*
    • MSSQL$BKUPEXEC
    • MSSQL$ECWDB2
    • MSSQL$PRACTICEMGT
    • MSSQL$PRACTTICEBGC
    • MSSQL$PROD
    • MSSQL$PROFXENGAGEMENT
    • MSSQL$SBSMONITORING
    • MSSQL$SHAREPOINT
    • MSSQL$SOPHOS
    • MSSQL$SQL_2008
    • MSSQL$SQLEXPRESS
    • MSSQL$SYSTEM_BGC
    • MSSQL$TPS
    • MSSQL$TPSAMA
    • MSSQL$VEEAMSQL2008R2
    • MSSQL$VEEAMSQL2012
    • MSSQLFDLauncher
    • MSSQLFDLauncher$PROFXENGAGEMENT
    • MSSQLFDLauncher$SBSMONITORING
    • MSSQLFDLauncher$SHAREPOINT
    • MSSQLFDLauncher$SQL_2008
    • MSSQLFDLauncher$SYSTEM_BGC
    • MSSQLFDLauncher$TPS
    • MSSQLFDLauncher$TPSAMA
    • MSSQLSERVER
    • MSSQLSERVER
    • MSSQLServerADHelper
    • MSSQLServerADHelper100
    • MSSQLServerOLAPService
    • MySQL57
    • NasPmService
    • OracleClientCache80
    • OSearch15
    • psqlWGE
    • QuickBooksDB25
    • RapidRecoveryAgent
    • ReportServer
    • ReportServer$*
    • ReportServer$SQL_2008
    • ReportServer$SYSTEM_BGC
    • ReportServer$TPS
    • ReportServer$TPSAMA
    • SPAdminV4
    • SPSearchHostController
    • SPTraceV4
    • SPUserCodeV4
    • SPWriterV4
    • SQLAgent$*
    • SQLAgent$BKUPEXEC
    • SQLAgent$CITRIX_METAFRAME
    • SQLAgent$CXDB
    • SQLAgent$ECWDB2
    • SQLAgent$PRACTTICEBGC
    • SQLAgent$PRACTTICEMGT
    • SQLAgent$PROD
    • SQLAgent$PROFXENGAGEMENT
    • SQLAgent$SBSMONITORING
    • SQLAgent$SHAREPOINT
    • SQLAgent$SOPHOS
    • SQLAgent$SQL_2008
    • SQLAgent$SQLEXPRESS
    • SQLAgent$SYSTEM_BGC
    • SQLAgent$TPS
    • SQLAgent$TPSAMA
    • SQLAgent$VEEAMSQL2008R2
    • SQLAgent$VEEAMSQL2012
    • SQLBackupAgent
    • SQLBackups
    • SQLBrowser
    • SQLsafe Backup Service
    • SQLSafeOLRService
    • SQLSERVERAGENT
    • SQLTELEMETRY
    • SQLWriter
    • stc_endpt_svc
    • swprv
    • Symantec System Recovery
    • SyncoveryVSSService
    • TeamViewer
    • TMBMServer
    • tmccsf
    • tmlisten
    • Veeam Backup Catalog Data Service
    • VeeamBackupSvc
    • VeeamCatalogSvc
    • VeeamCloudSvc
    • VeeamEndpointBackupSvc
    • VeeamEnterpriseManagerSvc
    • VeeamMountSvc
    • VeeamNFSSvc
    • VeeamRESTSvc
    • VeeamTransportSvc
    • vhdsvc
    • VSNAPVSS
    • wbengine
    • WinVNC4
    • wsbexchange
    • YTBackup
  • It encrypts all drives
  • It removes shared access on all drives

Ransomware Routine

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

  • bootm
  • boots
  • h0w_t0
  • iconca
  • ntuser

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

  • ahnlab
  • avast
  • avg
  • eset
  • hitman
  • kasper
  • mcafe
  • sophos
  • window

It avoids encrypting files found in the following folders:

  • $Recycle.Bin
  • All Users
  • Boot
  • Common Files
  • DVD Maker
  • Internet Explorer
  • Kaspersky Lab
  • Kaspersky Lab Setup Files
  • Microsoft
  • Microsoft.NET
  • Mozilla Firefox
  • MSBuild
  • PerfLogs
  • System Volume Information
  • Uninstall Information
  • Windows
  • Windows Defender
  • Windows Mail
  • Windows Media Player
  • Windows NT
  • Windows Photo Viewer
  • Windows Portable Devices
  • Windows Sidebar
  • WindowsApps
  • WindowsPowerShell

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

  • .pwnd

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

  • {Encrypted Directory}\H0w_T0_Rec0very_Files.txt
  • %Start Menu%\H0w_T0_Rec0very_Files.txt
  • %Application Data%\Microsoft\Windows\SendTo\H0w_T0_Rec0very_Files.txt
  • %Application Data%\Microsoft\Windows\Templates\H0w_T0_Rec0very_Files.txt
  • %Application Data%\Microsoft\Windows\Network Shortcuts\H0w_T0_Rec0very_Files.txt
  • %Application Data%\Microsoft\Windows\Printer Shortcuts\H0w_T0_Rec0very_Files.txt

It avoids encrypting files with the following file extensions:

  • .bac
  • .bak
  • .chm
  • .cmd
  • .dll
  • .exe
  • .hlf
  • .ico
  • .inf
  • .lng
  • .lnk
  • .msi
  • .sys
  • .ttf

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

15.792.04

FIRST VSAPI PATTERN DATE:

08 Apr 2020

VSAPI OPR PATTERN File:

15.793.00

VSAPI OPR PATTERN Date:

09 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

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 3

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 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}\H0w_T0_Rec0very_Files.txt
  • %Start Menu%\H0w_T0_Rec0very_Files.txt
  • %Application Data%\Microsoft\Windows\SendTo\H0w_T0_Rec0very_Files.txt
  • %Application Data%\Microsoft\Windows\Templates\H0w_T0_Rec0very_Files.txt
  • %Application Data%\Microsoft\Windows\Network Shortcuts\H0w_T0_Rec0very_Files.txt
  • %Application Data%\Microsoft\Windows\Printer Shortcuts\H0w_T0_Rec0very_Files.txt

Step 5

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • %All Users Profile%\boxed-join.avi
  • %All Users Profile%\clean.bat

Step 6

Restore encrypted files from backup.

Step 7

Scan your computer with your Trend Micro product to delete files detected as Ransom.Win32.PWNDLOCKER.B. 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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