Analysis Overview
SHA256
e737c901b80ad9ed2cd800fec7c2554178c8afab196fb55a0df36acda1324721
Threat Level: Known bad
The file decryptor.zip was found to be: Known bad.
Malicious Activity Summary
Avoslocker Ransomware
Enumerates physical storage devices
Modifies registry class
Suspicious use of SetWindowsHookEx
Suspicious use of WriteProcessMemory
MITRE ATT&CK
Enterprise Matrix V6
Analysis: static1
Detonation Overview
Reported
2022-01-12 07:04
Signatures
Analysis: behavioral1
Detonation Overview
Submitted
2022-01-12 07:04
Reported
2022-01-12 07:05
Platform
win7-en-20211208
Max time kernel
16s
Max time network
19s
Command Line
Signatures
Avoslocker Ransomware
Processes
C:\Users\Admin\AppData\Local\Temp\app\decryptor_avos2.exe
"C:\Users\Admin\AppData\Local\Temp\app\decryptor_avos2.exe"
Network
Files
Analysis: behavioral2
Detonation Overview
Submitted
2022-01-12 07:04
Reported
2022-01-12 07:05
Platform
win10-en-20211208
Max time kernel
15s
Max time network
21s
Command Line
Signatures
Avoslocker Ransomware
Processes
C:\Users\Admin\AppData\Local\Temp\app\decryptor_avos2.exe
"C:\Users\Admin\AppData\Local\Temp\app\decryptor_avos2.exe"
Network
| Country | Destination | Domain | Proto |
| IE | 52.109.76.30:443 | tcp | |
| US | 8.8.8.8:53 | time.windows.com | udp |
| US | 168.61.215.74:123 | time.windows.com | udp |
Files
Analysis: behavioral3
Detonation Overview
Submitted
2022-01-12 07:04
Reported
2022-01-12 07:05
Platform
win7-en-20211208
Max time kernel
14s
Max time network
17s
Command Line
Signatures
Enumerates physical storage devices
Modifies registry class
| Description | Indicator | Process | Target |
| Set value (str) | \REGISTRY\USER\S-1-5-21-3846991908-3261386348-1409841751-1000_CLASSES\.elf\ = "elf_auto_file" | C:\Windows\system32\rundll32.exe | N/A |
| Key created | \REGISTRY\USER\S-1-5-21-3846991908-3261386348-1409841751-1000_CLASSES\elf_auto_file\shell | C:\Windows\system32\rundll32.exe | N/A |
| Set value (str) | \REGISTRY\USER\S-1-5-21-3846991908-3261386348-1409841751-1000_CLASSES\elf_auto_file\shell\Read\command\ = "\"C:\\Program Files (x86)\\Adobe\\Reader 9.0\\Reader\\AcroRd32.exe\" \"%1\"" | C:\Windows\system32\rundll32.exe | N/A |
| Key created | \REGISTRY\USER\S-1-5-21-3846991908-3261386348-1409841751-1000_Classes\Local Settings | C:\Windows\system32\rundll32.exe | N/A |
| Key created | \REGISTRY\USER\S-1-5-21-3846991908-3261386348-1409841751-1000_CLASSES\Local Settings\Software\Microsoft\Windows\Shell\MuiCache | C:\Windows\system32\rundll32.exe | N/A |
| Key created | \REGISTRY\USER\S-1-5-21-3846991908-3261386348-1409841751-1000_CLASSES\elf_auto_file | C:\Windows\system32\rundll32.exe | N/A |
| Set value (str) | \REGISTRY\USER\S-1-5-21-3846991908-3261386348-1409841751-1000_CLASSES\elf_auto_file\ | C:\Windows\system32\rundll32.exe | N/A |
| Key created | \REGISTRY\USER\S-1-5-21-3846991908-3261386348-1409841751-1000_CLASSES\.elf | C:\Windows\system32\rundll32.exe | N/A |
| Key created | \REGISTRY\USER\S-1-5-21-3846991908-3261386348-1409841751-1000_CLASSES\elf_auto_file\shell\Read | C:\Windows\system32\rundll32.exe | N/A |
| Key created | \REGISTRY\USER\S-1-5-21-3846991908-3261386348-1409841751-1000_CLASSES\elf_auto_file\shell\Read\command | C:\Windows\system32\rundll32.exe | N/A |
Suspicious use of SetWindowsHookEx
| Description | Indicator | Process | Target |
| N/A | N/A | C:\Program Files (x86)\Adobe\Reader 9.0\Reader\AcroRd32.exe | N/A |
| N/A | N/A | C:\Program Files (x86)\Adobe\Reader 9.0\Reader\AcroRd32.exe | N/A |
Suspicious use of WriteProcessMemory
| Description | Indicator | Process | Target |
| PID 1540 wrote to memory of 756 | N/A | C:\Windows\system32\cmd.exe | C:\Windows\system32\rundll32.exe |
| PID 1540 wrote to memory of 756 | N/A | C:\Windows\system32\cmd.exe | C:\Windows\system32\rundll32.exe |
| PID 1540 wrote to memory of 756 | N/A | C:\Windows\system32\cmd.exe | C:\Windows\system32\rundll32.exe |
| PID 756 wrote to memory of 1644 | N/A | C:\Windows\system32\rundll32.exe | C:\Program Files (x86)\Adobe\Reader 9.0\Reader\AcroRd32.exe |
| PID 756 wrote to memory of 1644 | N/A | C:\Windows\system32\rundll32.exe | C:\Program Files (x86)\Adobe\Reader 9.0\Reader\AcroRd32.exe |
| PID 756 wrote to memory of 1644 | N/A | C:\Windows\system32\rundll32.exe | C:\Program Files (x86)\Adobe\Reader 9.0\Reader\AcroRd32.exe |
| PID 756 wrote to memory of 1644 | N/A | C:\Windows\system32\rundll32.exe | C:\Program Files (x86)\Adobe\Reader 9.0\Reader\AcroRd32.exe |
Processes
C:\Windows\system32\cmd.exe
cmd /c C:\Users\Admin\AppData\Local\Temp\app\linux\decryptor.elf
C:\Windows\system32\rundll32.exe
"C:\Windows\system32\rundll32.exe" C:\Windows\system32\shell32.dll,OpenAs_RunDLL C:\Users\Admin\AppData\Local\Temp\app\linux\decryptor.elf
C:\Program Files (x86)\Adobe\Reader 9.0\Reader\AcroRd32.exe
"C:\Program Files (x86)\Adobe\Reader 9.0\Reader\AcroRd32.exe" "C:\Users\Admin\AppData\Local\Temp\app\linux\decryptor.elf"
Network
Files
memory/1540-54-0x000007FEFBE91000-0x000007FEFBE93000-memory.dmp
memory/756-55-0x0000000000000000-mapping.dmp
memory/1644-57-0x0000000000000000-mapping.dmp
memory/1644-58-0x0000000075891000-0x0000000075893000-memory.dmp
Analysis: behavioral4
Detonation Overview
Submitted
2022-01-12 07:04
Reported
2022-01-12 07:05
Platform
win10-en-20211208
Max time kernel
14s
Max time network
21s
Command Line
Signatures
Enumerates physical storage devices
Modifies registry class
| Description | Indicator | Process | Target |
| Key created | \REGISTRY\USER\S-1-5-21-2361464256-2201551969-2316606395-1000_Classes\Local Settings | C:\Windows\system32\cmd.exe | N/A |
| Key created | \REGISTRY\USER\S-1-5-21-2361464256-2201551969-2316606395-1000_Classes\Local Settings | C:\Windows\system32\OpenWith.exe | N/A |
Suspicious use of SetWindowsHookEx
| Description | Indicator | Process | Target |
| N/A | N/A | C:\Windows\system32\OpenWith.exe | N/A |
Processes
C:\Windows\system32\cmd.exe
cmd /c C:\Users\Admin\AppData\Local\Temp\app\linux\decryptor.elf
C:\Windows\system32\OpenWith.exe
C:\Windows\system32\OpenWith.exe -Embedding
Network
| Country | Destination | Domain | Proto |
| US | 52.109.8.19:443 | tcp | |
| US | 8.8.8.8:53 | time.windows.com | udp |
| NL | 40.119.148.38:123 | time.windows.com | udp |