Analysis
- max time kernel
104s - max time network
131s - platform
windows10-2004_x64 - resource
win10v2004-20220812-en - resource tags
- submitted
11/10/2022, 02:21
General
- Target a07762926413974d6a5e39c3a5a467cf.exe
- Size 3.2MB
- Sample221011-cszzrsagc8
- SHA256 8c7e227bdb4c0b55dfd41b29614bd1b852132c65ec90a564ebf67230d421abc8
Malware Config
Signatures
- DcRat
DarkCrystal(DC) is a new .NET RAT active since June 2019 capable of loading additional plugins.
- Modifies WinLogon for persistence 2 TTPs 1 IoCs
- Process spawned unexpected child process 3 IoCs
This typically indicates the parent process was compromised via an exploit or macro.
- DCRat payload 5 IoCs
Detects payload of DCRat, commonly dropped by NSIS installers.
- Executes dropped EXE 1 IoCs
- Checks computer location settings 2 TTPs 1 IoCs
Looks up country code configured in the registry, likely geofence.
- Adds Run key to start application 2 TTPs 2 IoCs
- Suspicious use of NtSetInformationThreadHideFromDebugger 11 IoCs
- Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s). Likely ransomware behaviour.
- Creates scheduled task(s) 1 TTPs 3 IoCs
Schtasks is often used by malware for persistence or to perform post-infection execution.
- Suspicious behavior: EnumeratesProcesses 2 IoCs
- Suspicious use of AdjustPrivilegeToken 2 IoCs
- Suspicious use of SetWindowsHookEx 2 IoCs
- Suspicious use of WriteProcessMemory 3 IoCs
Processes
-
C:\Users\Admin\AppData\Local\Temp\a07762926413974d6a5e39c3a5a467cf.exe"C:\Users\Admin\AppData\Local\Temp\a07762926413974d6a5e39c3a5a467cf.exe"1⤵
- Modifies WinLogon for persistence
- Checks computer location settings
- Adds Run key to start application
- Suspicious use of NtSetInformationThreadHideFromDebugger
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
-
C:\Users\Admin\AppData\Local\spoolsv.exe"C:\Users\Admin\AppData\Local\spoolsv.exe"2⤵
- Executes dropped EXE
- Suspicious use of NtSetInformationThreadHideFromDebugger
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of SetWindowsHookEx
-
-
C:\Windows\system32\schtasks.exeschtasks.exe /create /tn "spoolsvs" /sc MINUTE /mo 8 /tr "'C:/Users/Admin/AppData/Local/\spoolsv.exe'" /f1⤵
- Process spawned unexpected child process
- Creates scheduled task(s)
-
C:\Windows\system32\schtasks.exeschtasks.exe /create /tn "spoolsv" /sc ONLOGON /tr "'C:/Users/Admin/AppData/Local/\spoolsv.exe'" /rl HIGHEST /f1⤵
- Process spawned unexpected child process
- Creates scheduled task(s)
-
C:\Windows\system32\schtasks.exeschtasks.exe /create /tn "spoolsvs" /sc MINUTE /mo 12 /tr "'C:/Users/Admin/AppData/Local/\spoolsv.exe'" /rl HIGHEST /f1⤵
- Process spawned unexpected child process
- Creates scheduled task(s)
Network
MITRE ATT&CK Enterprise v6
Replay Monitor
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Downloads
spoolsv.exe
spoolsv.exe
memory/428-144-0x0000000000EF0000-0x00000000014B8000-memory.dmp
memory/428-148-0x0000000000EF0000-0x00000000014B8000-memory.dmp
memory/428-147-0x0000000000EF0000-0x00000000014B8000-memory.dmp
memory/428-146-0x0000000000EF0000-0x00000000014B8000-memory.dmp
memory/428-143-0x0000000000EF0000-0x00000000014B8000-memory.dmp
memory/824-134-0x00000000064C0000-0x0000000006A64000-memory.dmp
memory/824-135-0x0000000000430000-0x00000000009F8000-memory.dmp
memory/824-133-0x0000000000430000-0x00000000009F8000-memory.dmp
memory/824-139-0x0000000006B20000-0x0000000006B86000-memory.dmp
memory/824-132-0x0000000000430000-0x00000000009F8000-memory.dmp
memory/824-145-0x0000000000430000-0x00000000009F8000-memory.dmp
memory/824-138-0x0000000006FA0000-0x00000000074CC000-memory.dmp
memory/824-137-0x00000000062D0000-0x0000000006362000-memory.dmp
memory/824-136-0x0000000006190000-0x00000000061E0000-memory.dmp