Malware Analysis Report

2024-10-16 03:26

Sample ID 231219-mkvp7acdgl
Target 075cb88f83fbe4ad2ae0f553697e7bdf
SHA256 be19681b21f2a573b477444a788e00eb8dad2d740d11c02f14e878fe5b89fa70
Tags
avoslocker ransomware
score
10/10

Table of Contents

Analysis Overview

MITRE ATT&CK

Enterprise Matrix V15

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

be19681b21f2a573b477444a788e00eb8dad2d740d11c02f14e878fe5b89fa70

Threat Level: Known bad

The file 075cb88f83fbe4ad2ae0f553697e7bdf was found to be: Known bad.

Malicious Activity Summary

avoslocker ransomware

Avoslocker Ransomware

Renames multiple (144) files with added filename extension

Renames multiple (185) files with added filename extension

Sets desktop wallpaper using registry

Unsigned PE

Suspicious use of AdjustPrivilegeToken

Suspicious use of WriteProcessMemory

Suspicious behavior: EnumeratesProcesses

MITRE ATT&CK

Analysis: static1

Detonation Overview

Reported

2023-12-19 10:31

Signatures

Unsigned PE

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

Analysis: behavioral1

Detonation Overview

Submitted

2023-12-19 10:31

Reported

2023-12-19 12:05

Platform

win7-20231215-en

Max time kernel

122s

Max time network

128s

Command Line

"C:\Users\Admin\AppData\Local\Temp\075cb88f83fbe4ad2ae0f553697e7bdf.exe"

Signatures

Avoslocker Ransomware

ransomware avoslocker

Renames multiple (185) files with added filename extension

ransomware

Sets desktop wallpaper using registry

ransomware
Description Indicator Process Target
Set value (str) \REGISTRY\USER\S-1-5-21-3427588347-1492276948-3422228430-1000\Control Panel\Desktop\Wallpaper = "C:\\Users\\Admin\\AppData\\Local\\Temp\\113589822.png" C:\Windows\SysWOW64\reg.exe N/A

Suspicious behavior: EnumeratesProcesses

Description Indicator Process Target
N/A N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe N/A

Suspicious use of AdjustPrivilegeToken

Description Indicator Process Target
Token: SeDebugPrivilege N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe N/A

Suspicious use of WriteProcessMemory

Description Indicator Process Target
PID 2972 wrote to memory of 2296 N/A C:\Users\Admin\AppData\Local\Temp\075cb88f83fbe4ad2ae0f553697e7bdf.exe C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
PID 2972 wrote to memory of 2296 N/A C:\Users\Admin\AppData\Local\Temp\075cb88f83fbe4ad2ae0f553697e7bdf.exe C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
PID 2972 wrote to memory of 2296 N/A C:\Users\Admin\AppData\Local\Temp\075cb88f83fbe4ad2ae0f553697e7bdf.exe C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
PID 2972 wrote to memory of 2296 N/A C:\Users\Admin\AppData\Local\Temp\075cb88f83fbe4ad2ae0f553697e7bdf.exe C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
PID 2296 wrote to memory of 880 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\reg.exe
PID 2296 wrote to memory of 880 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\reg.exe
PID 2296 wrote to memory of 880 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\reg.exe
PID 2296 wrote to memory of 880 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\reg.exe
PID 2296 wrote to memory of 1568 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe
PID 2296 wrote to memory of 1568 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe
PID 2296 wrote to memory of 1568 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe
PID 2296 wrote to memory of 1568 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe
PID 2296 wrote to memory of 1568 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe
PID 2296 wrote to memory of 1568 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe
PID 2296 wrote to memory of 1568 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe

Processes

C:\Users\Admin\AppData\Local\Temp\075cb88f83fbe4ad2ae0f553697e7bdf.exe

"C:\Users\Admin\AppData\Local\Temp\075cb88f83fbe4ad2ae0f553697e7bdf.exe"

C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe

powershell -Command "$a = [System.IO.File]::ReadAllText(\"C:\GET_YOUR_FILES_BACK.txt\");Add-Type -AssemblyName System.Drawing;$filename = \"$env:temp\$(Get-Random).png\";$bmp = new-object System.Drawing.Bitmap 1920,1080;$font = new-object System.Drawing.Font Consolas,10;$brushBg = [System.Drawing.Brushes]::Black;$brushFg = [System.Drawing.Brushes]::White;$format = [System.Drawing.StringFormat]::GenericDefault;$format.Alignment = [System.Drawing.StringAlignment]::Center;$format.LineAlignment = [System.Drawing.StringAlignment]::Center;$graphics = [System.Drawing.Graphics]::FromImage($bmp);$graphics.FillRectangle($brushBg,0,0,$bmp.Width,$bmp.Height);$graphics.DrawString($a,$font,$brushFg,[System.Drawing.RectangleF]::FromLTRB(0, 0, 1920, 1080),$format);$graphics.Dispose();$bmp.Save($filename);reg add \"HKEY_CURRENT_USER\Control Panel\Desktop\" /v Wallpaper /t REG_SZ /d $filename /f;Start-Sleep 1;rundll32.exe user32.dll, UpdatePerUserSystemParameters, 0, $false;"

C:\Windows\SysWOW64\reg.exe

"C:\Windows\system32\reg.exe" add "HKEY_CURRENT_USER\Control Panel\Desktop" /v Wallpaper /t REG_SZ /d C:\Users\Admin\AppData\Local\Temp\113589822.png /f

C:\Windows\SysWOW64\rundll32.exe

"C:\Windows\system32\rundll32.exe" user32.dll UpdatePerUserSystemParameters 0 False

Network

N/A

Files

C:\Users\GET_YOUR_FILES_BACK.txt

MD5 d90d05a5fea9c28b3bf2b55f808c3a45
SHA1 7774c79c85b4401acfc56002f9e8a3e10e8a7b60
SHA256 8a9b224d68a718e7cd4da069a158408d9c71fb8ecc4e4a6581982d7a35b29cec
SHA512 783d830a0d75911da6878ea58f7191f1438a429e232c63db86e6f09a1bb390ec7ee72f10db1ee695177686cacab24c9e58f61e7d403d75dd9c817c592131170a

memory/2296-449-0x00000000738E0000-0x0000000073E8B000-memory.dmp

memory/2296-450-0x00000000738E0000-0x0000000073E8B000-memory.dmp

memory/2296-451-0x0000000002340000-0x0000000002380000-memory.dmp

memory/2296-452-0x0000000002340000-0x0000000002380000-memory.dmp

memory/2296-453-0x0000000002340000-0x0000000002380000-memory.dmp

memory/2296-456-0x00000000738E0000-0x0000000073E8B000-memory.dmp

Analysis: behavioral2

Detonation Overview

Submitted

2023-12-19 10:31

Reported

2023-12-19 12:07

Platform

win10v2004-20231215-en

Max time kernel

142s

Max time network

150s

Command Line

"C:\Users\Admin\AppData\Local\Temp\075cb88f83fbe4ad2ae0f553697e7bdf.exe"

Signatures

Avoslocker Ransomware

ransomware avoslocker

Renames multiple (144) files with added filename extension

ransomware

Sets desktop wallpaper using registry

ransomware
Description Indicator Process Target
Set value (str) \REGISTRY\USER\S-1-5-21-996941297-2279405024-2328152752-1000\Control Panel\Desktop\Wallpaper = "C:\\Users\\Admin\\AppData\\Local\\Temp\\681291657.png" C:\Windows\SysWOW64\reg.exe N/A

Suspicious behavior: EnumeratesProcesses

Description Indicator Process Target
N/A N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe N/A
N/A N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe N/A

Suspicious use of AdjustPrivilegeToken

Description Indicator Process Target
Token: SeDebugPrivilege N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe N/A

Processes

C:\Users\Admin\AppData\Local\Temp\075cb88f83fbe4ad2ae0f553697e7bdf.exe

"C:\Users\Admin\AppData\Local\Temp\075cb88f83fbe4ad2ae0f553697e7bdf.exe"

C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe

powershell -Command "$a = [System.IO.File]::ReadAllText(\"C:\GET_YOUR_FILES_BACK.txt\");Add-Type -AssemblyName System.Drawing;$filename = \"$env:temp\$(Get-Random).png\";$bmp = new-object System.Drawing.Bitmap 1920,1080;$font = new-object System.Drawing.Font Consolas,10;$brushBg = [System.Drawing.Brushes]::Black;$brushFg = [System.Drawing.Brushes]::White;$format = [System.Drawing.StringFormat]::GenericDefault;$format.Alignment = [System.Drawing.StringAlignment]::Center;$format.LineAlignment = [System.Drawing.StringAlignment]::Center;$graphics = [System.Drawing.Graphics]::FromImage($bmp);$graphics.FillRectangle($brushBg,0,0,$bmp.Width,$bmp.Height);$graphics.DrawString($a,$font,$brushFg,[System.Drawing.RectangleF]::FromLTRB(0, 0, 1920, 1080),$format);$graphics.Dispose();$bmp.Save($filename);reg add \"HKEY_CURRENT_USER\Control Panel\Desktop\" /v Wallpaper /t REG_SZ /d $filename /f;Start-Sleep 1;rundll32.exe user32.dll, UpdatePerUserSystemParameters, 0, $false;"

C:\Windows\SysWOW64\reg.exe

"C:\Windows\system32\reg.exe" add "HKEY_CURRENT_USER\Control Panel\Desktop" /v Wallpaper /t REG_SZ /d C:\Users\Admin\AppData\Local\Temp\681291657.png /f

C:\Windows\SysWOW64\rundll32.exe

"C:\Windows\system32\rundll32.exe" user32.dll UpdatePerUserSystemParameters 0 False

Network

Country Destination Domain Proto
US 138.91.171.81:80 tcp
US 8.8.8.8:53 21.53.126.40.in-addr.arpa udp
US 8.8.8.8:53 206.178.17.96.in-addr.arpa udp
US 8.8.8.8:53 9.228.82.20.in-addr.arpa udp
US 8.8.8.8:53 0.159.190.20.in-addr.arpa udp
US 8.8.8.8:53 95.221.229.192.in-addr.arpa udp
US 8.8.8.8:53 55.36.223.20.in-addr.arpa udp
US 8.8.8.8:53 41.110.16.96.in-addr.arpa udp
US 8.8.8.8:53 183.59.114.20.in-addr.arpa udp
US 8.8.8.8:53 18.31.95.13.in-addr.arpa udp
US 8.8.8.8:53 178.223.142.52.in-addr.arpa udp
US 8.8.8.8:53 181.178.17.96.in-addr.arpa udp
US 8.8.8.8:53 14.227.111.52.in-addr.arpa udp
US 8.8.8.8:53 193.78.101.95.in-addr.arpa udp
US 8.8.8.8:53 10.173.189.20.in-addr.arpa udp

Files

C:\GET_YOUR_FILES_BACK.txt

MD5 d90d05a5fea9c28b3bf2b55f808c3a45
SHA1 7774c79c85b4401acfc56002f9e8a3e10e8a7b60
SHA256 8a9b224d68a718e7cd4da069a158408d9c71fb8ecc4e4a6581982d7a35b29cec
SHA512 783d830a0d75911da6878ea58f7191f1438a429e232c63db86e6f09a1bb390ec7ee72f10db1ee695177686cacab24c9e58f61e7d403d75dd9c817c592131170a

memory/5308-407-0x0000000074730000-0x0000000074EE0000-memory.dmp

memory/5308-408-0x0000000002A30000-0x0000000002A40000-memory.dmp

memory/5308-409-0x0000000002E60000-0x0000000002E96000-memory.dmp

memory/5308-410-0x0000000005530000-0x0000000005B58000-memory.dmp

memory/5308-411-0x0000000005BB0000-0x0000000005BD2000-memory.dmp

memory/5308-412-0x0000000005CD0000-0x0000000005D36000-memory.dmp

memory/5308-413-0x0000000005DF0000-0x0000000005E56000-memory.dmp

C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_c1glbve5.nz5.ps1

MD5 d17fe0a3f47be24a6453e9ef58c94641
SHA1 6ab83620379fc69f80c0242105ddffd7d98d5d9d
SHA256 96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7
SHA512 5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

memory/5308-423-0x0000000005F60000-0x00000000062B4000-memory.dmp

memory/5308-424-0x0000000006450000-0x000000000646E000-memory.dmp

memory/5308-425-0x0000000006490000-0x00000000064DC000-memory.dmp

memory/5308-427-0x0000000002A30000-0x0000000002A40000-memory.dmp

memory/5308-429-0x00000000069A0000-0x00000000069BA000-memory.dmp

memory/5308-428-0x0000000007C50000-0x00000000082CA000-memory.dmp

memory/5308-430-0x0000000007820000-0x00000000078B2000-memory.dmp

memory/5308-434-0x0000000074730000-0x0000000074EE0000-memory.dmp