Malware Analysis Report

2024-10-16 03:27

Sample ID 240105-cswbksgbbr
Target f810deb1ba171cea5b595c6d3f816127fb182833f7a08a98de93226d4f6a336f.zip
SHA256 d3470cbf411c34cb8fd2b21b7ab70ece9aff8b28e7b50722013ebfcfb26c954b
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

d3470cbf411c34cb8fd2b21b7ab70ece9aff8b28e7b50722013ebfcfb26c954b

Threat Level: Known bad

The file f810deb1ba171cea5b595c6d3f816127fb182833f7a08a98de93226d4f6a336f.zip was found to be: Known bad.

Malicious Activity Summary

avoslocker ransomware

Avoslocker Ransomware

Renames multiple (198) files with added filename extension

Renames multiple (136) files with added filename extension

Sets desktop wallpaper using registry

Unsigned PE

Suspicious use of AdjustPrivilegeToken

Suspicious use of WriteProcessMemory

Opens file in notepad (likely ransom note)

Suspicious behavior: EnumeratesProcesses

MITRE ATT&CK

Analysis: static1

Detonation Overview

Reported

2024-01-05 02:20

Signatures

Unsigned PE

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

Analysis: behavioral1

Detonation Overview

Submitted

2024-01-05 02:20

Reported

2024-01-05 02:23

Platform

win7-20231129-en

Max time kernel

118s

Max time network

119s

Command Line

"C:\Users\Admin\AppData\Local\Temp\f810deb1ba171cea5b595c6d3f816127fb182833f7a08a98de93226d4f6a336f.exe"

Signatures

Avoslocker Ransomware

ransomware avoslocker

Renames multiple (198) files with added filename extension

ransomware

Sets desktop wallpaper using registry

ransomware
Description Indicator Process Target
Set value (str) \REGISTRY\USER\S-1-5-21-3627615824-4061627003-3019543961-1000\Control Panel\Desktop\Wallpaper = "C:\\Users\\Admin\\AppData\\Local\\Temp\\496767467.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 2232 wrote to memory of 1540 N/A C:\Users\Admin\AppData\Local\Temp\f810deb1ba171cea5b595c6d3f816127fb182833f7a08a98de93226d4f6a336f.exe C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
PID 2232 wrote to memory of 1540 N/A C:\Users\Admin\AppData\Local\Temp\f810deb1ba171cea5b595c6d3f816127fb182833f7a08a98de93226d4f6a336f.exe C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
PID 2232 wrote to memory of 1540 N/A C:\Users\Admin\AppData\Local\Temp\f810deb1ba171cea5b595c6d3f816127fb182833f7a08a98de93226d4f6a336f.exe C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
PID 2232 wrote to memory of 1540 N/A C:\Users\Admin\AppData\Local\Temp\f810deb1ba171cea5b595c6d3f816127fb182833f7a08a98de93226d4f6a336f.exe C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
PID 1540 wrote to memory of 2404 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\reg.exe
PID 1540 wrote to memory of 2404 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\reg.exe
PID 1540 wrote to memory of 2404 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\reg.exe
PID 1540 wrote to memory of 2404 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\reg.exe
PID 1540 wrote to memory of 884 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe
PID 1540 wrote to memory of 884 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe
PID 1540 wrote to memory of 884 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe
PID 1540 wrote to memory of 884 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe
PID 1540 wrote to memory of 884 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe
PID 1540 wrote to memory of 884 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe
PID 1540 wrote to memory of 884 N/A C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe C:\Windows\SysWOW64\rundll32.exe

Processes

C:\Users\Admin\AppData\Local\Temp\f810deb1ba171cea5b595c6d3f816127fb182833f7a08a98de93226d4f6a336f.exe

"C:\Users\Admin\AppData\Local\Temp\f810deb1ba171cea5b595c6d3f816127fb182833f7a08a98de93226d4f6a336f.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\496767467.png /f

C:\Windows\SysWOW64\rundll32.exe

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

Network

N/A

Files

C:\GET_YOUR_FILES_BACK.txt

MD5 ee4b9494cf5b7402768b8db4a0f233c9
SHA1 9b5ea1e4fe997a6e9a6981d6f1d651557ad9c213
SHA256 f2161f906bed19f6a79f0bbe7919e3526baa5cf0080055e5aa84b50094a1278c
SHA512 29ef4199f16348262e3828991eca8608b340849e7c480ae469f36c7e1ed8995f5d63d0c66d7316dc9690148322b56164a707731122212b1669b7764c93e5f356

memory/1540-477-0x00000000028E0000-0x0000000002920000-memory.dmp

memory/1540-479-0x00000000028E0000-0x0000000002920000-memory.dmp

memory/1540-478-0x0000000073CC0000-0x000000007426B000-memory.dmp

memory/1540-476-0x0000000073CC0000-0x000000007426B000-memory.dmp

memory/1540-483-0x0000000073CC0000-0x000000007426B000-memory.dmp

C:\Users\Admin\AppData\Local\Temp\496767467.png

MD5 52ebab915b3b7a577375a83f5a112e35
SHA1 9b77c770b7c02c2720a5f57068f19d654ad80ca2
SHA256 70d9b340bff370de621141e814f78994f6d757ce17178b28e8c9d5f478d5d3a5
SHA512 b93e40508078eaac3c5d6d78ca04cf029f0fd83cb93aa8919c27b999e231b511201bfb2f8c2f4faa9f8b253b187f5415bb9e03f7db5d425ff2df11ffd4da98fe

Analysis: behavioral2

Detonation Overview

Submitted

2024-01-05 02:20

Reported

2024-01-05 02:24

Platform

win10v2004-20231215-en

Max time kernel

170s

Max time network

180s

Command Line

"C:\Users\Admin\AppData\Local\Temp\f810deb1ba171cea5b595c6d3f816127fb182833f7a08a98de93226d4f6a336f.exe"

Signatures

Avoslocker Ransomware

ransomware avoslocker

Renames multiple (136) files with added filename extension

ransomware

Opens file in notepad (likely ransom note)

ransomware
Description Indicator Process Target
N/A N/A C:\Windows\system32\NOTEPAD.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\f810deb1ba171cea5b595c6d3f816127fb182833f7a08a98de93226d4f6a336f.exe

"C:\Users\Admin\AppData\Local\Temp\f810deb1ba171cea5b595c6d3f816127fb182833f7a08a98de93226d4f6a336f.exe"

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

powershell -Command "$a = [System.IO.File]::ReadAllText(\"F:\GET_YOUR_FILES_BACK.txt\");Add-Type -AssemblyName System.Drawing;$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\system32\NOTEPAD.EXE

"C:\Windows\system32\NOTEPAD.EXE" C:\Users\Admin\Desktop\GET_YOUR_FILES_BACK.txt

Network

Country Destination Domain Proto
US 8.8.8.8:53 21.53.126.40.in-addr.arpa udp
US 8.8.8.8:53 95.221.229.192.in-addr.arpa udp
US 8.8.8.8:53 241.154.82.20.in-addr.arpa udp
US 8.8.8.8:53 43.58.199.20.in-addr.arpa udp
US 8.8.8.8:53 85.177.190.20.in-addr.arpa udp
US 8.8.8.8:53 41.110.16.96.in-addr.arpa udp
US 8.8.8.8:53 208.194.73.20.in-addr.arpa udp
US 8.8.8.8:53 183.59.114.20.in-addr.arpa udp
US 8.8.8.8:53 15.164.165.52.in-addr.arpa udp
US 8.8.8.8:53 18.134.221.88.in-addr.arpa udp
US 8.8.8.8:53 43.229.111.52.in-addr.arpa udp
US 8.8.8.8:53 0.204.248.87.in-addr.arpa udp
US 8.8.8.8:53 158.240.127.40.in-addr.arpa udp
US 8.8.8.8:53 180.178.17.96.in-addr.arpa udp
US 8.8.8.8:53 2.136.104.51.in-addr.arpa udp
US 8.8.8.8:53 136.71.105.51.in-addr.arpa udp
US 8.8.8.8:53 tse1.mm.bing.net udp
US 204.79.197.200:443 tse1.mm.bing.net tcp
US 204.79.197.200:443 tse1.mm.bing.net tcp

Files

F:\$RECYCLE.BIN\GET_YOUR_FILES_BACK.txt

MD5 ee4b9494cf5b7402768b8db4a0f233c9
SHA1 9b5ea1e4fe997a6e9a6981d6f1d651557ad9c213
SHA256 f2161f906bed19f6a79f0bbe7919e3526baa5cf0080055e5aa84b50094a1278c
SHA512 29ef4199f16348262e3828991eca8608b340849e7c480ae469f36c7e1ed8995f5d63d0c66d7316dc9690148322b56164a707731122212b1669b7764c93e5f356

memory/6112-389-0x0000000074B40000-0x00000000752F0000-memory.dmp

memory/6112-390-0x0000000004B50000-0x0000000004B60000-memory.dmp

memory/6112-391-0x00000000029E0000-0x0000000002A16000-memory.dmp

memory/6112-392-0x0000000004B50000-0x0000000004B60000-memory.dmp

memory/6112-393-0x0000000005190000-0x00000000057B8000-memory.dmp

memory/6112-394-0x0000000074B40000-0x00000000752F0000-memory.dmp

memory/6112-395-0x0000000004B50000-0x0000000004B60000-memory.dmp

memory/6112-396-0x0000000004F00000-0x0000000004F22000-memory.dmp

memory/6112-397-0x00000000050A0000-0x0000000005106000-memory.dmp

memory/6112-398-0x0000000005830000-0x0000000005896000-memory.dmp

memory/6112-399-0x0000000004B50000-0x0000000004B60000-memory.dmp

C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_wao2lhd5.czh.ps1

MD5 d17fe0a3f47be24a6453e9ef58c94641
SHA1 6ab83620379fc69f80c0242105ddffd7d98d5d9d
SHA256 96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7
SHA512 5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

memory/6112-405-0x0000000005A20000-0x0000000005D74000-memory.dmp

memory/6112-411-0x0000000005FF0000-0x000000000600E000-memory.dmp

memory/6112-412-0x00000000060C0000-0x000000000610C000-memory.dmp

memory/6112-414-0x0000000004B50000-0x0000000004B60000-memory.dmp

memory/6112-415-0x0000000007670000-0x0000000007CEA000-memory.dmp