dcrat | d9cbcae95ae824014b6d2fd6d3269b00b09ab84ed44b45b21c0b1842e7cdc132

General

Target
DCRatBuild.exe
Size 1.1MB
Sample241116-mlb98svdnd
SHA256 d9cbcae95ae824014b6d2fd6d3269b00b09ab84ed44b45b21c0b1842e7cdc132
MD5 7ef93a29c05d412dd2dc432e1aac54a9
SHA1 776cc5c36f370a7e1fa840a21c13f2278723409e
SHA512 26e00619e47a130fb768b91074915c8a69f8690ac12465f21c1bd7e69f94ae6db9a238ff3c510a719cf1a318a07c80a543212c200b2b2152934a1ad154d13ab6
SSDEEP 12288:URZ+IoG/n9IQxW3OBseUUT+tcYbv+RK+UfXST5/rKMyFckcb8M41AT0z/GAFPz3m:u2G/nvxW3WieC7STuMMATKPTVgxr4q
MD5 SHA1 SHA512 SSDEEP

Score

10^/10

dcrat discovery infostealer persistence rat

Malware Config

Signatures

DcRat
DarkCrystal(DC) is a new .NET RAT active since June 2019 capable of loading additional plugins.
rat infostealer dcrat
Dcrat family
dcrat

Modifies WinLogon for persistence 2 TTPs 4 IoCs

persistence

Winlogon Helper DLL

T1547.004

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\Recovery\\20e7eb62-69f6-11ef-be0c-62cb582c238c\\lsass.exe\""	Bridgewebsvc.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\Recovery\\20e7eb62-69f6-11ef-be0c-62cb582c238c\\lsass.exe\", \"C:\\Program Files\\DVD Maker\\es-ES\\taskhost.exe\""	Bridgewebsvc.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\Recovery\\20e7eb62-69f6-11ef-be0c-62cb582c238c\\lsass.exe\", \"C:\\Program Files\\DVD Maker\\es-ES\\taskhost.exe\", \"C:\\Program Files (x86)\\Microsoft Sync Framework\\v1.0\\Documentation\\cmd.exe\""	Bridgewebsvc.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\Recovery\\20e7eb62-69f6-11ef-be0c-62cb582c238c\\lsass.exe\", \"C:\\Program Files\\DVD Maker\\es-ES\\taskhost.exe\", \"C:\\Program Files (x86)\\Microsoft Sync Framework\\v1.0\\Documentation\\cmd.exe\", \"C:\\Recovery\\20e7eb62-69f6-11ef-be0c-62cb582c238c\\services.exe\""	Bridgewebsvc.exe

Process spawned unexpected child process 12 IoCs

This typically indicates the parent process was compromised via an exploit or macro.

description	pid	pid_target	Process	procid_target
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2860	2664	schtasks.exe	35
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2884	2664	schtasks.exe	35
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2700	2664	schtasks.exe	35
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	1468	2664	schtasks.exe	35
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2552	2664	schtasks.exe	35
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2608	2664	schtasks.exe	35
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2092	2664	schtasks.exe	35
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	3024	2664	schtasks.exe	35
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	1020	2664	schtasks.exe	35
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	1104	2664	schtasks.exe	35
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2800	2664	schtasks.exe	35
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	1864	2664	schtasks.exe	35

DCRat payload 3 IoCs

Detects payload of DCRat, commonly dropped by NSIS installers.

rat

resource	yara_rule
behavioral1/files/0x0008000000016d3a-9.dat	dcrat
behavioral1/memory/2676-13-0x00000000010C0000-0x0000000001196000-memory.dmp	dcrat
behavioral1/memory/1596-28-0x0000000001380000-0x0000000001456000-memory.dmp	dcrat

Executes dropped EXE 2 IoCs

pid	Process
2676	Bridgewebsvc.exe
1596	cmd.exe

Loads dropped DLL 2 IoCs

pid	Process
2400	cmd.exe
2400	cmd.exe

Adds Run key to start application 2 TTPs 8 IoCs

persistence

Registry Run Keys / Startup Folder

T1547.001

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\USER\S-1-5-21-2872745919-2748461613-2989606286-1000\Software\Microsoft\Windows\CurrentVersion\Run\cmd = "\"C:\\Program Files (x86)\\Microsoft Sync Framework\\v1.0\\Documentation\\cmd.exe\""	Bridgewebsvc.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\cmd = "\"C:\\Program Files (x86)\\Microsoft Sync Framework\\v1.0\\Documentation\\cmd.exe\""	Bridgewebsvc.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-2872745919-2748461613-2989606286-1000\Software\Microsoft\Windows\CurrentVersion\Run\services = "\"C:\\Recovery\\20e7eb62-69f6-11ef-be0c-62cb582c238c\\services.exe\""	Bridgewebsvc.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\services = "\"C:\\Recovery\\20e7eb62-69f6-11ef-be0c-62cb582c238c\\services.exe\""	Bridgewebsvc.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-2872745919-2748461613-2989606286-1000\Software\Microsoft\Windows\CurrentVersion\Run\lsass = "\"C:\\Recovery\\20e7eb62-69f6-11ef-be0c-62cb582c238c\\lsass.exe\""	Bridgewebsvc.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\lsass = "\"C:\\Recovery\\20e7eb62-69f6-11ef-be0c-62cb582c238c\\lsass.exe\""	Bridgewebsvc.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-2872745919-2748461613-2989606286-1000\Software\Microsoft\Windows\CurrentVersion\Run\taskhost = "\"C:\\Program Files\\DVD Maker\\es-ES\\taskhost.exe\""	Bridgewebsvc.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\taskhost = "\"C:\\Program Files\\DVD Maker\\es-ES\\taskhost.exe\""	Bridgewebsvc.exe

Drops file in Program Files directory 4 IoCs

description	ioc	Process
File created	C:\Program Files\DVD Maker\es-ES\taskhost.exe	Bridgewebsvc.exe
File created	C:\Program Files\DVD Maker\es-ES\b75386f1303e64	Bridgewebsvc.exe
File created	C:\Program Files (x86)\Microsoft Sync Framework\v1.0\Documentation\cmd.exe	Bridgewebsvc.exe
File created	C:\Program Files (x86)\Microsoft Sync Framework\v1.0\Documentation\ebf1f9fa8afd6d	Bridgewebsvc.exe

Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s).

System Information Discovery
T1082

System Location Discovery: System Language Discovery 1 TTPs 3 IoCs

Attempt gather information about the system language of a victim in order to infer the geographical location of that host.

discovery

System Language Discovery

T1614.001

description	ioc	Process
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	DCRatBuild.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	WScript.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe

Scheduled Task/Job: Scheduled Task 1 TTPs 12 IoCs

Schtasks is often used by malware for persistence or to perform post-infection execution.

persistence execution

Scheduled Task

T1053.005

pid	Process
2700	schtasks.exe
2092	schtasks.exe
1020	schtasks.exe
2800	schtasks.exe
2860	schtasks.exe
2884	schtasks.exe
1468	schtasks.exe
2552	schtasks.exe
2608	schtasks.exe
3024	schtasks.exe
1104	schtasks.exe
1864	schtasks.exe

Suspicious behavior: EnumeratesProcesses 2 IoCs

pid	Process
2676	Bridgewebsvc.exe
1596	cmd.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	2676	Bridgewebsvc.exe
Token: SeDebugPrivilege	1596	cmd.exe

Suspicious use of WriteProcessMemory 15 IoCs

description	pid	Process	procid_target
PID 1992 wrote to memory of 2280	1992	DCRatBuild.exe	31
PID 1992 wrote to memory of 2280	1992	DCRatBuild.exe	31
PID 1992 wrote to memory of 2280	1992	DCRatBuild.exe	31
PID 1992 wrote to memory of 2280	1992	DCRatBuild.exe	31
PID 2280 wrote to memory of 2400	2280	WScript.exe	32
PID 2280 wrote to memory of 2400	2280	WScript.exe	32
PID 2280 wrote to memory of 2400	2280	WScript.exe	32
PID 2280 wrote to memory of 2400	2280	WScript.exe	32
PID 2400 wrote to memory of 2676	2400	cmd.exe	34
PID 2400 wrote to memory of 2676	2400	cmd.exe	34
PID 2400 wrote to memory of 2676	2400	cmd.exe	34
PID 2400 wrote to memory of 2676	2400	cmd.exe	34
PID 2676 wrote to memory of 1596	2676	Bridgewebsvc.exe	48
PID 2676 wrote to memory of 1596	2676	Bridgewebsvc.exe	48
PID 2676 wrote to memory of 1596	2676	Bridgewebsvc.exe	48

Uses Task Scheduler COM API 1 TTPs
The Task Scheduler COM API can be used to schedule applications to run on boot or at set times.
persistence

Query Registry
T1012

C:\Users\Admin\AppData\Local\Temp\DCRatBuild.exe
"C:\Users\Admin\AppData\Local\Temp\DCRatBuild.exe"
1⤵
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:1992
- C:\Windows\SysWOW64\WScript.exe
  "C:\Windows\System32\WScript.exe" "C:\PortproviderRuntime\2jiE6dDNxF2hUpVE5Z.vbe"
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:2280
- - C:\Windows\SysWOW64\cmd.exe
    cmd /c ""C:\PortproviderRuntime\OI2YygSphQCiiCNA7ofzvo.bat" "
    3⤵
    - Loads dropped DLL
    - System Location Discovery: System Language Discovery
    - Suspicious use of WriteProcessMemory
    PID:2400
  - - C:\PortproviderRuntime\Bridgewebsvc.exe
      "C:\PortproviderRuntime\Bridgewebsvc.exe"
      4⤵
      Modifies WinLogon for persistence
      Executes dropped EXE
      Adds Run key to start application
      Drops file in Program Files directory
      Suspicious behavior: EnumeratesProcesses
      Suspicious use of AdjustPrivilegeToken
      Suspicious use of WriteProcessMemory
      PID:2676
    - - C:\Program Files (x86)\Microsoft Sync Framework\v1.0\Documentation\cmd.exe
        
        "C:\Program Files (x86)\Microsoft Sync Framework\v1.0\Documentation\cmd.exe"
        5⤵
        Executes dropped EXE
        Suspicious behavior: EnumeratesProcesses
        Suspicious use of AdjustPrivilegeToken
        
        PID:1596

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "lsassl" /sc MINUTE /mo 6 /tr "'C:\Recovery\20e7eb62-69f6-11ef-be0c-62cb582c238c\lsass.exe'" /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2860

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "lsass" /sc ONLOGON /tr "'C:\Recovery\20e7eb62-69f6-11ef-be0c-62cb582c238c\lsass.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2884

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "lsassl" /sc MINUTE /mo 12 /tr "'C:\Recovery\20e7eb62-69f6-11ef-be0c-62cb582c238c\lsass.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2700

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "taskhostt" /sc MINUTE /mo 6 /tr "'C:\Program Files\DVD Maker\es-ES\taskhost.exe'" /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:1468

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "taskhost" /sc ONLOGON /tr "'C:\Program Files\DVD Maker\es-ES\taskhost.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2552

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "taskhostt" /sc MINUTE /mo 14 /tr "'C:\Program Files\DVD Maker\es-ES\taskhost.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2608

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "cmdc" /sc MINUTE /mo 9 /tr "'C:\Program Files (x86)\Microsoft Sync Framework\v1.0\Documentation\cmd.exe'" /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2092

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "cmd" /sc ONLOGON /tr "'C:\Program Files (x86)\Microsoft Sync Framework\v1.0\Documentation\cmd.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:3024

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "cmdc" /sc MINUTE /mo 10 /tr "'C:\Program Files (x86)\Microsoft Sync Framework\v1.0\Documentation\cmd.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:1020

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "servicess" /sc MINUTE /mo 14 /tr "'C:\Recovery\20e7eb62-69f6-11ef-be0c-62cb582c238c\services.exe'" /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:1104

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "services" /sc ONLOGON /tr "'C:\Recovery\20e7eb62-69f6-11ef-be0c-62cb582c238c\services.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2800

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "servicess" /sc MINUTE /mo 6 /tr "'C:\Recovery\20e7eb62-69f6-11ef-be0c-62cb582c238c\services.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:1864

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Persistence

Boot or Logon Autostart Execution

2

T1547

Registry Run Keys / Startup Folder

1

T1547.001

Winlogon Helper DLL

1

T1547.004

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Privilege Escalation

Boot or Logon Autostart Execution

2

T1547

Registry Run Keys / Startup Folder

1

T1547.001

Winlogon Helper DLL

1

T1547.004

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Defense Evasion

Modify Registry

2

T1112

Credential Access

Discovery

Query Registry

1

T1012

System Information Discovery

1

T1082

System Location Discovery

1

T1614

System Language Discovery

1

T1614.001

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

2jiE6dDNxF2hUpVE5Z.vbe

Path C:\PortproviderRuntime\2jiE6dDNxF2hUpVE5Z.vbe
Size 218B
SHA256 2e118668b3c63457b924aafd6b402e105477030d6157e3d66ba8ba7acad58dcf
MD5 413767cf51f36f7f50d9430d73ea0bb1
SHA1 4469733bce94a114c836ea3591dccb3e689782c7
SHA512 3c12a46412227f57f8aa815b0b7820ca54eb3fa7a033ea7baa7efad7526755db7998d843a6790880efa87b841e9c6085b793930ae865c2694c8385e5937ee900
MD5 SHA1 SHA512

Submit Download

OI2YygSphQCiiCNA7ofzvo.bat

Path C:\PortproviderRuntime\OI2YygSphQCiiCNA7ofzvo.bat
Size 41B
SHA256 d4fa2e3203a21efd9f46fd9ea5fcedbabe13bd9a2bc93d0169070507380bbf9b
MD5 863d81db66a0a5864890665ea50c23c5
SHA1 f5a584f4ee5e390b667eaa5e5d9332251388fa7e
SHA512 ecb8ff338e0febcfe8965516a58dcdcd63420592467ce1c281f7ccacf7a2ca02bd7a73d52208e98edec3e73ea69477f3ccaa4ddf4b0608e5598a92e110e5d3b0
MD5 SHA1 SHA512

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Bridgewebsvc.exe

Path \PortproviderRuntime\Bridgewebsvc.exe
Size 828KB
SHA256 f014b4dd1600fb5ecd92de55165573415c2d7ee184a4f70f2f975ee7909150f6
MD5 fddea23e803e9e5de212e4c0475c8f93
SHA1 c4426bf36ce54917155da2bfbec1508c5a799664
SHA512 05459fc75998ee306e8de7e544aaf744e5c6e1930dcb7e02b94a566a7ad6e874a9fe50a78a1da50b4e7110282e49353f8ced586117d772b600b84d09ee070591
SSDEEP 12288:F+RK+UfXST5/rKMyFckcb8M41AT0z/GAFPz3DhsHxrofdV:5STuMMATKPTVgxr4
MD5 SHA1 SHA512 SSDEEP

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memory/1596-28-0x0000000001380000-0x0000000001456000-memory.dmp

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memory/2676-13-0x00000000010C0000-0x0000000001196000-memory.dmp

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Resubmissions

Analysis

Sharing

General

Malware Config

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads