Malware Analysis Report

2024-09-11 07:13

Sample ID 240529-tb8c9aba8z
Target MrsMajor3.0.exe
SHA256 b6ef7d7410a44494a09973b7b0ca173ca4f67f52ea542c7393e3d1874257dfb5
Tags
discovery evasion exploit persistence ransomware trojan
score
10/10

Table of Contents

Analysis Overview

MITRE ATT&CK Matrix

Analysis: static1

Detonation Overview

Signatures

Analysis: behavioral1

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis: behavioral2

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis Overview

score
10/10

SHA256

b6ef7d7410a44494a09973b7b0ca173ca4f67f52ea542c7393e3d1874257dfb5

Threat Level: Known bad

The file MrsMajor3.0.exe was found to be: Known bad.

Malicious Activity Summary

discovery evasion exploit persistence ransomware trojan

Modifies WinLogon for persistence

UAC bypass

Disables Task Manager via registry modification

Possible privilege escalation attempt

Checks computer location settings

Modifies file permissions

Sets desktop wallpaper using registry

Drops file in Windows directory

Unsigned PE

Enumerates physical storage devices

Modifies Control Panel

Modifies data under HKEY_USERS

Suspicious use of SetWindowsHookEx

System policy modification

Suspicious use of WriteProcessMemory

Suspicious use of AdjustPrivilegeToken

MITRE ATT&CK Matrix V13

Initial Access
TA0001
Execution
TA0002
Persistence
TA0003
Boot or Logon Autostart Execution
T1547
Winlogon Helper DLL
T1547.004
Privilege Escalation
TA0004
Boot or Logon Autostart Execution
T1547
Winlogon Helper DLL
T1547.004
Abuse Elevation Control Mechanism
T1548
Bypass User Account Control
T1548.002
Defense Evasion
TA0005
Modify Registry
T1112
Abuse Elevation Control Mechanism
T1548
Bypass User Account Control
T1548.002
Impair Defenses
T1562
Disable or Modify Tools
T1562.001
File and Directory Permissions Modification
T1222
Credential Access
TA0006
Discovery
TA0007
System Information Discovery
T1082
Query Registry
T1012
Lateral Movement
TA0008
Collection
TA0009
Exfiltration
TA0010
Command and Control
TA0011
Impact
TA0040
Defacement
T1491
Resource Development
TA0042
Reconnaissance
TA0043

Analysis: static1

Detonation Overview

Reported

2024-05-29 15:54

Signatures

Unsigned PE

Description Indicator Process Target
N/A N/A N/A N/A

Analysis: behavioral1

Detonation Overview

Submitted

2024-05-29 15:54

Reported

2024-05-29 15:54

Platform

win7-20240419-en

Max time kernel

7s

Max time network

8s

Command Line

"C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe"

Signatures

Modifies WinLogon for persistence

persistence
Description Indicator Process Target
Set value (str) \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, wscript.exe \"C:\\windows\\winbase_base_procid_none\\secureloc0x65\\WinRapistI386.vbs\"" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

UAC bypass

evasion trojan
Description Indicator Process Target
Set value (int) \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\ConsentPromptBehaviorAdmin = "0" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

Disables Task Manager via registry modification

evasion

Possible privilege escalation attempt

exploit
Description Indicator Process Target
N/A N/A C:\windows\system32\takeown.exe N/A
N/A N/A C:\windows\system32\icacls.exe N/A

Modifies file permissions

discovery
Description Indicator Process Target
N/A N/A C:\windows\system32\takeown.exe N/A
N/A N/A C:\windows\system32\icacls.exe N/A

Sets desktop wallpaper using registry

ransomware
Description Indicator Process Target
Set value (str) \REGISTRY\USER\S-1-5-21-481678230-3773327859-3495911762-1000\Control Panel\Desktop\Wallpaper = "C:\\Users\\Admin\\AppData\\Local\\Temp\\\\wlp.tmp" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

Drops file in Windows directory

Description Indicator Process Target
File opened for modification C:\windows\winbase_base_procid_none\secureloc0x65\mainbgtheme.wav C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
File opened for modification C:\windows\winbase_base_procid_none\secureloc0x65\WinRapistI386.vbs C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
File opened for modification C:\windows\winbase_base_procid_none\secureloc0x65\rcur.cur C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
File opened for modification C:\windows\winbase_base_procid_none\secureloc0x65\ui65.exe C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
File opened for modification C:\windows\winbase_base_procid_none\secureloc0x65\logonuiOWR.exe C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
File opened for modification C:\windows\winbase_base_procid_none\secureloc0x65\gdifuncs.exe C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

Enumerates physical storage devices

Modifies Control Panel

evasion
Description Indicator Process Target
Set value (str) \REGISTRY\USER\S-1-5-21-481678230-3773327859-3495911762-1000\Control Panel\Cursors\Arrow = "C:\\Windows\\winbase_base_procid_none\\secureloc0x65\\rcur.cur" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
Set value (str) \REGISTRY\USER\S-1-5-21-481678230-3773327859-3495911762-1000\Control Panel\Cursors\AppStarting = "C:\\Windows\\winbase_base_procid_none\\secureloc0x65\\rcur.cur" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
Set value (str) \REGISTRY\USER\S-1-5-21-481678230-3773327859-3495911762-1000\Control Panel\Cursors\Hand = "C:\\Windows\\winbase_base_procid_none\\secureloc0x65\\rcur.cur" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

Suspicious use of AdjustPrivilegeToken

Description Indicator Process Target
Token: SeShutdownPrivilege N/A C:\Windows\System32\shutdown.exe N/A
Token: SeRemoteShutdownPrivilege N/A C:\Windows\System32\shutdown.exe N/A

Suspicious use of WriteProcessMemory

Description Indicator Process Target
PID 2220 wrote to memory of 1800 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\windows\system32\takeown.exe
PID 2220 wrote to memory of 1800 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\windows\system32\takeown.exe
PID 2220 wrote to memory of 1800 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\windows\system32\takeown.exe
PID 2220 wrote to memory of 2148 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\windows\system32\icacls.exe
PID 2220 wrote to memory of 2148 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\windows\system32\icacls.exe
PID 2220 wrote to memory of 2148 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\windows\system32\icacls.exe
PID 2220 wrote to memory of 2672 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\Windows\System32\shutdown.exe
PID 2220 wrote to memory of 2672 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\Windows\System32\shutdown.exe
PID 2220 wrote to memory of 2672 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\Windows\System32\shutdown.exe

System policy modification

evasion
Description Indicator Process Target
Set value (int) \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\ConsentPromptBehaviorAdmin = "0" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

Processes

C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe

"C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe"

C:\windows\system32\takeown.exe

"C:\windows\system32\takeown.exe" /f C:\

C:\windows\system32\icacls.exe

"C:\windows\system32\icacls.exe" C:\ /granted "Admin":F

C:\Windows\System32\shutdown.exe

"C:\Windows\System32\shutdown.exe" /r /t 00

C:\Windows\system32\LogonUI.exe

"LogonUI.exe" /flags:0x0

C:\Windows\system32\LogonUI.exe

"LogonUI.exe" /flags:0x1

Network

N/A

Files

memory/2220-0-0x000007FEF4EB3000-0x000007FEF4EB4000-memory.dmp

memory/2220-1-0x0000000000900000-0x0000000001F04000-memory.dmp

memory/2768-10-0x0000000002F60000-0x0000000002F61000-memory.dmp

Analysis: behavioral2

Detonation Overview

Submitted

2024-05-29 15:54

Reported

2024-05-29 15:54

Platform

win10v2004-20240426-en

Max time kernel

8s

Max time network

10s

Command Line

"C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe"

Signatures

Modifies WinLogon for persistence

persistence
Description Indicator Process Target
Set value (str) \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, wscript.exe \"C:\\windows\\winbase_base_procid_none\\secureloc0x65\\WinRapistI386.vbs\"" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

UAC bypass

evasion trojan
Description Indicator Process Target
Set value (int) \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\ConsentPromptBehaviorAdmin = "0" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

Disables Task Manager via registry modification

evasion

Possible privilege escalation attempt

exploit
Description Indicator Process Target
N/A N/A C:\windows\system32\takeown.exe N/A
N/A N/A C:\windows\system32\icacls.exe N/A

Checks computer location settings

Description Indicator Process Target
Key value queried \REGISTRY\USER\S-1-5-21-4018855536-2201274732-320770143-1000\Control Panel\International\Geo\Nation C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

Modifies file permissions

discovery
Description Indicator Process Target
N/A N/A C:\windows\system32\takeown.exe N/A
N/A N/A C:\windows\system32\icacls.exe N/A

Sets desktop wallpaper using registry

ransomware
Description Indicator Process Target
Set value (str) \REGISTRY\USER\S-1-5-21-4018855536-2201274732-320770143-1000\Control Panel\Desktop\Wallpaper = "C:\\Users\\Admin\\AppData\\Local\\Temp\\\\wlp.tmp" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

Drops file in Windows directory

Description Indicator Process Target
File opened for modification C:\windows\winbase_base_procid_none\secureloc0x65\WinRapistI386.vbs C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
File opened for modification C:\windows\winbase_base_procid_none\secureloc0x65\rcur.cur C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
File opened for modification C:\windows\winbase_base_procid_none\secureloc0x65\ui65.exe C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
File opened for modification C:\windows\winbase_base_procid_none\secureloc0x65\logonuiOWR.exe C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
File opened for modification C:\windows\winbase_base_procid_none\secureloc0x65\gdifuncs.exe C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
File opened for modification C:\windows\winbase_base_procid_none\secureloc0x65\mainbgtheme.wav C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

Enumerates physical storage devices

Modifies Control Panel

evasion
Description Indicator Process Target
Set value (str) \REGISTRY\USER\S-1-5-21-4018855536-2201274732-320770143-1000\Control Panel\Cursors\Arrow = "C:\\Windows\\winbase_base_procid_none\\secureloc0x65\\rcur.cur" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
Set value (str) \REGISTRY\USER\S-1-5-21-4018855536-2201274732-320770143-1000\Control Panel\Cursors\AppStarting = "C:\\Windows\\winbase_base_procid_none\\secureloc0x65\\rcur.cur" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A
Set value (str) \REGISTRY\USER\S-1-5-21-4018855536-2201274732-320770143-1000\Control Panel\Cursors\Hand = "C:\\Windows\\winbase_base_procid_none\\secureloc0x65\\rcur.cur" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

Modifies data under HKEY_USERS

Description Indicator Process Target
Set value (data) \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Explorer\Accent\AccentPalette = a6d8ff0076b9ed00429ce3000078d700005a9e000042750000264200f7630c00 C:\Windows\system32\LogonUI.exe N/A
Key created \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Themes\History C:\Windows\system32\LogonUI.exe N/A
Key created \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM C:\Windows\system32\LogonUI.exe N/A
Set value (int) \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\AccentColor = "4292311040" C:\Windows\system32\LogonUI.exe N/A
Set value (int) \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\ColorizationColor = "3288365271" C:\Windows\system32\LogonUI.exe N/A
Key created \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Explorer\Accent C:\Windows\system32\LogonUI.exe N/A
Set value (int) \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Explorer\Accent\AccentColorMenu = "4292311040" C:\Windows\system32\LogonUI.exe N/A
Set value (int) \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\ColorizationAfterglow = "3288365271" C:\Windows\system32\LogonUI.exe N/A
Set value (int) \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\ColorizationGlassAttribute = "1" C:\Windows\system32\LogonUI.exe N/A
Set value (int) \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\ColorizationColorBalance = "89" C:\Windows\system32\LogonUI.exe N/A
Set value (int) \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\ColorizationBlurBalance = "1" C:\Windows\system32\LogonUI.exe N/A
Set value (int) \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\EnableWindowColorization = "237" C:\Windows\system32\LogonUI.exe N/A
Set value (int) \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Themes\History\AutoColor = "0" C:\Windows\system32\LogonUI.exe N/A
Set value (int) \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Explorer\Accent\StartColorMenu = "4288567808" C:\Windows\system32\LogonUI.exe N/A
Set value (int) \REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\ColorizationAfterglowBalance = "10" C:\Windows\system32\LogonUI.exe N/A

Suspicious use of AdjustPrivilegeToken

Description Indicator Process Target
Token: SeShutdownPrivilege N/A C:\Windows\System32\shutdown.exe N/A
Token: SeRemoteShutdownPrivilege N/A C:\Windows\System32\shutdown.exe N/A

Suspicious use of SetWindowsHookEx

Description Indicator Process Target
N/A N/A C:\Windows\system32\LogonUI.exe N/A

Suspicious use of WriteProcessMemory

Description Indicator Process Target
PID 4524 wrote to memory of 860 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\windows\system32\takeown.exe
PID 4524 wrote to memory of 860 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\windows\system32\takeown.exe
PID 4524 wrote to memory of 4360 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\windows\system32\icacls.exe
PID 4524 wrote to memory of 4360 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\windows\system32\icacls.exe
PID 4524 wrote to memory of 4596 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\Windows\System32\shutdown.exe
PID 4524 wrote to memory of 4596 N/A C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe C:\Windows\System32\shutdown.exe

System policy modification

evasion
Description Indicator Process Target
Set value (int) \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\ConsentPromptBehaviorAdmin = "0" C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe N/A

Processes

C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe

"C:\Users\Admin\AppData\Local\Temp\MrsMajor3.0.exe"

C:\windows\system32\takeown.exe

"C:\windows\system32\takeown.exe" /f C:\

C:\windows\system32\icacls.exe

"C:\windows\system32\icacls.exe" C:\ /granted "Admin":F

C:\Windows\System32\shutdown.exe

"C:\Windows\System32\shutdown.exe" /r /t 00

C:\Windows\system32\LogonUI.exe

"LogonUI.exe" /flags:0x4 /state0:0xa399e855 /state1:0x41c64e6d

Network

Country Destination Domain Proto
US 8.8.8.8:53 149.220.183.52.in-addr.arpa udp
US 8.8.8.8:53 144.107.17.2.in-addr.arpa udp
US 8.8.8.8:53 71.31.126.40.in-addr.arpa udp
US 8.8.8.8:53 8.173.189.20.in-addr.arpa udp

Files

memory/4524-0-0x00007FF9D8F23000-0x00007FF9D8F25000-memory.dmp

memory/4524-1-0x00000000003F0000-0x00000000019F4000-memory.dmp