dcrat | 9cf6cd197d923c4806912e9c5ef08e3c2c50fb4b20d4ab8b15590a88b73f296b

General

Target

{VKK+KODS}/Vkk.exe
Size

164KB
MD5

c417467a71603bf9373d85720947aa53
SHA1

14d819592c4c5a287f8237fbae8afb136a58404d
SHA256

99e670906e0585ff8b380ed79e5c4a299ca46dc7d121f79513c9710c89925a64
SHA512

ae768d8473121ca4ecaa2593dc4425b3ddf7ff712f34749c69dbd3fef1e8dc74207df2e0647a8e430dc7662e8c7a96f4e39abcf88de83d9fb4c402734c47e1e1
SSDEEP

3072:yT62kltl7utrZ8KIw4T3k69nhTaRGAQyeFo:yTwzlP3kwnBAfQVF

Score

10^/10

dcrat discovery infostealer 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

Process spawned unexpected child process 9 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	2904	2908	schtasks.exe	34
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2816	2908	schtasks.exe	34
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2684	2908	schtasks.exe	34
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2780	2908	schtasks.exe	34
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2592	2908	schtasks.exe	34
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	1708	2908	schtasks.exe	34
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2580	2908	schtasks.exe	34
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2632	2908	schtasks.exe	34
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	3024	2908	schtasks.exe	34

DCRat payload 3 IoCs

Detects payload of DCRat, commonly dropped by NSIS installers.

rat

resource	yara_rule
behavioral1/files/0x00070000000190c6-9.dat	dcrat
behavioral1/memory/2988-13-0x0000000001140000-0x0000000001196000-memory.dmp	dcrat
behavioral1/memory/1308-27-0x0000000000820000-0x0000000000876000-memory.dmp	dcrat

Executes dropped EXE 2 IoCs

pid	Process
2988	BridgeMsDll.exe
1308	csrss.exe

Loads dropped DLL 2 IoCs

pid	Process
2536	cmd.exe
2536	cmd.exe

Drops file in Program Files directory 2 IoCs

description	ioc	Process
File created	C:\Program Files\Common Files\SpeechEngines\Microsoft\explorer.exe	BridgeMsDll.exe
File created	C:\Program Files\Common Files\SpeechEngines\Microsoft\7a0fd90576e088	BridgeMsDll.exe

Drops file in Windows directory 3 IoCs

description	ioc	Process
File created	C:\Windows\DigitalLocker\es-ES\csrss.exe	BridgeMsDll.exe
File opened for modification	C:\Windows\DigitalLocker\es-ES\csrss.exe	BridgeMsDll.exe
File created	C:\Windows\DigitalLocker\es-ES\886983d96e3d3e	BridgeMsDll.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	WScript.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	Vkk.exe

Scheduled Task/Job: Scheduled Task 1 TTPs 9 IoCs

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

persistence execution

Scheduled Task

T1053.005

pid	Process
2904	schtasks.exe
2780	schtasks.exe
2632	schtasks.exe
3024	schtasks.exe
2816	schtasks.exe
2684	schtasks.exe
2592	schtasks.exe
1708	schtasks.exe
2580	schtasks.exe

Suspicious behavior: EnumeratesProcesses 2 IoCs

pid	Process
2988	BridgeMsDll.exe
1308	csrss.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	2988	BridgeMsDll.exe
Token: SeDebugPrivilege	1308	csrss.exe

Suspicious use of WriteProcessMemory 21 IoCs

description	pid	Process	procid_target
PID 2496 wrote to memory of 2072	2496	Vkk.exe	30
PID 2496 wrote to memory of 2072	2496	Vkk.exe	30
PID 2496 wrote to memory of 2072	2496	Vkk.exe	30
PID 2496 wrote to memory of 2072	2496	Vkk.exe	30
PID 2072 wrote to memory of 2536	2072	WScript.exe	31
PID 2072 wrote to memory of 2536	2072	WScript.exe	31
PID 2072 wrote to memory of 2536	2072	WScript.exe	31
PID 2072 wrote to memory of 2536	2072	WScript.exe	31
PID 2536 wrote to memory of 2988	2536	cmd.exe	33
PID 2536 wrote to memory of 2988	2536	cmd.exe	33
PID 2536 wrote to memory of 2988	2536	cmd.exe	33
PID 2536 wrote to memory of 2988	2536	cmd.exe	33
PID 2988 wrote to memory of 2044	2988	BridgeMsDll.exe	44
PID 2988 wrote to memory of 2044	2988	BridgeMsDll.exe	44
PID 2988 wrote to memory of 2044	2988	BridgeMsDll.exe	44
PID 2044 wrote to memory of 2312	2044	cmd.exe	46
PID 2044 wrote to memory of 2312	2044	cmd.exe	46
PID 2044 wrote to memory of 2312	2044	cmd.exe	46
PID 2044 wrote to memory of 1308	2044	cmd.exe	48
PID 2044 wrote to memory of 1308	2044	cmd.exe	48
PID 2044 wrote to memory of 1308	2044	cmd.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\{VKK+KODS}\Vkk.exe
"C:\Users\Admin\AppData\Local\Temp\{VKK+KODS}\Vkk.exe"
1⤵
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:2496
- C:\Windows\SysWOW64\WScript.exe
  "C:\Windows\System32\WScript.exe" "C:\Combrowser\Fcaxb7I9ITZe2hUWU.vbe"
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:2072
- - C:\Windows\SysWOW64\cmd.exe
    cmd /c ""C:\Combrowser\10l79m1i778n.bat" "
    3⤵
    - Loads dropped DLL
    - System Location Discovery: System Language Discovery
    - Suspicious use of WriteProcessMemory
    PID:2536
  - - C:\Combrowser\BridgeMsDll.exe
      "C:\Combrowser\BridgeMsDll.exe"
      4⤵
      Executes dropped EXE
      Drops file in Program Files directory
      Drops file in Windows directory
      Suspicious behavior: EnumeratesProcesses
      Suspicious use of AdjustPrivilegeToken
      Suspicious use of WriteProcessMemory
      PID:2988
    - - C:\Windows\System32\cmd.exe
        
        "C:\Windows\System32\cmd.exe" /C "C:\Users\Admin\AppData\Local\Temp\59Xk1BDvn8.bat"
        5⤵
        Suspicious use of WriteProcessMemory
        
        PID:2044
      - C:\Windows\system32\w32tm.exe
        
        w32tm /stripchart /computer:localhost /period:5 /dataonly /samples:2
        6⤵
        
        PID:2312
      - C:\Windows\DigitalLocker\es-ES\csrss.exe
        
        "C:\Windows\DigitalLocker\es-ES\csrss.exe"
        6⤵
        Executes dropped EXE
        Suspicious behavior: EnumeratesProcesses
        Suspicious use of AdjustPrivilegeToken
        
        PID:1308

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "csrssc" /sc MINUTE /mo 12 /tr "'C:\Windows\DigitalLocker\es-ES\csrss.exe'" /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2904

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "csrss" /sc ONLOGON /tr "'C:\Windows\DigitalLocker\es-ES\csrss.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2816

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "csrssc" /sc MINUTE /mo 10 /tr "'C:\Windows\DigitalLocker\es-ES\csrss.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2684

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "taskhostt" /sc MINUTE /mo 11 /tr "'C:\Combrowser\taskhost.exe'" /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2780

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "taskhost" /sc ONLOGON /tr "'C:\Combrowser\taskhost.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2592

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "taskhostt" /sc MINUTE /mo 11 /tr "'C:\Combrowser\taskhost.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:1708

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "explorere" /sc MINUTE /mo 13 /tr "'C:\Program Files\Common Files\SpeechEngines\Microsoft\explorer.exe'" /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2580

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "explorer" /sc ONLOGON /tr "'C:\Program Files\Common Files\SpeechEngines\Microsoft\explorer.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2632

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "explorere" /sc MINUTE /mo 9 /tr "'C:\Program Files\Common Files\SpeechEngines\Microsoft\explorer.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:3024

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Persistence

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Privilege Escalation

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Defense Evasion

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

C:\Combrowser\10l79m1i778n.bat

Filesize
31B

MD5
e229e6475655dbf48debe39ea7e4c0d0

SHA1
835a9dc7bd837e6096df8d97dff90ab88e656a41

SHA256
0ef204e2c7f3c6d5ace003c6864db74cc2f085543409a3366af99a5f45823933

SHA512
6aa3ae4bf881de134b54ca4e5f813ed380645091a51762046b41d47e56318a3970a5b4158d302fc887e0ccff41304050364acde8fcf0e126721e0eea1bc42b27

Download Submit
C:\Combrowser\Fcaxb7I9ITZe2hUWU.vbe

Filesize
199B

MD5
75cec359961d378447f24b18efadc0c5

SHA1
9fec81fc93c8d8b17a4070057ec8e68da824c14d

SHA256
cb4216925fc61c39e18644995303fc6b6eedd4154ce6b10a6e42a71db8170101

SHA512
1f0f57c0a11485c656c49d8b897e101660775e8cd7c35c2cb302dabc9bd9024bfd173d7a938f733b12d30636715238325ea6fa4955e344822c512ff4ab030597

Download Submit
C:\Users\Admin\AppData\Local\Temp\59Xk1BDvn8.bat

Filesize
205B

MD5
bed6364b25f849ba6ed199e347b0f605

SHA1
e3c0b5bf95298d879edae72b874c94940fada899

SHA256
1b9d13415ba0e81af611faef6f8cb4aa1378c981802f9f9aeb25256d294aa210

SHA512
f99e9169ec03da38363c8fb77e8c0e180d0e702336e867486c2779d410affb993f14d009fa185cdf1b29c168c1be1acc2b45dcd19da4d657f36eeace5d7e16bc

Download Submit
\Combrowser\BridgeMsDll.exe

Filesize
315KB

MD5
57566762e7d37fdeae9c4740f16f1b75

SHA1
e6d5a1055d1064569977dc54f5ba162348e2bebb

SHA256
ea420c16fb24ec295eca3c796d735a758bdc00071d233ff73ee841d56b4b004a

SHA512
0d94f11242de7f01804e9e35fd5f422be6bcc62a292d900aa708b01c74472e2bee20dfc682786c88dd26d97614d00b2fc5106b7557d4eff090487ca7032f8783

Download Submit
memory/1308-27-0x0000000000820000-0x0000000000876000-memory.dmp

Filesize
344KB

Download
memory/2988-13-0x0000000001140000-0x0000000001196000-memory.dmp

Filesize
344KB

Download

Analysis

Sharing

General

Malware Config

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads