Analysis Overview
SHA256
be19681b21f2a573b477444a788e00eb8dad2d740d11c02f14e878fe5b89fa70
Threat Level: Known bad
The file 075cb88f83fbe4ad2ae0f553697e7bdf was found to be: Known bad.
Malicious Activity Summary
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
Enterprise Matrix V15
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
Signatures
Avoslocker Ransomware
Renames multiple (185) files with added filename extension
Sets desktop wallpaper using registry
| 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
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
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
Signatures
Avoslocker Ransomware
Renames multiple (144) files with added filename extension
Sets desktop wallpaper using registry
| 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 |
Suspicious use of WriteProcessMemory
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