dcrat | 6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9b

General

Target

6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9bN.exe
Size

7.3MB
MD5

ba51fe0a806fde9a0a548d5c944ade50
SHA1

1763951e46fce5ded1faac1328cd409ae38d5cee
SHA256

6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9b
SHA512

d9a23b4aa23d187f6b432edca418251e76dc7c9e8e0688fd7f7ad853acf88629c377784073cc97e5e04fc664d999d64fe3ea49089b3b463656467889dd1f8269
SSDEEP

196608:rTn3WAWbD9PX/xS1m5YTdzCfjQGkbCGhpwdmVQ:rjCP9PX/xUm+TgjQPCGtK

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

Process spawned unexpected child process 5 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	648	1752	schtasks.exe	92
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	3020	1752	schtasks.exe	92
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	3376	1752	schtasks.exe	92
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	1432	1752	schtasks.exe	92
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	3204	1752	schtasks.exe	92

DCRat payload 3 IoCs

Detects payload of DCRat, commonly dropped by NSIS installers.

rat

resource	yara_rule
behavioral2/files/0x000b000000023ba4-15.dat	dcrat
behavioral2/files/0x000a000000023baa-38.dat	dcrat
behavioral2/memory/5044-40-0x0000000000BA0000-0x0000000000DE8000-memory.dmp	dcrat

Drops file in Drivers directory 1 IoCs

description	ioc	Process
File opened for modification	C:\Windows\System32\drivers\etc\hosts	taskhostw.exe

Checks computer location settings 2 TTPs 4 IoCs

Looks up country code configured in the registry, likely geofence.

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key value queried	\REGISTRY\USER\S-1-5-21-2437139445-1151884604-3026847218-1000\Control Panel\International\Geo\Nation	6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9bN.exe
Key value queried	\REGISTRY\USER\S-1-5-21-2437139445-1151884604-3026847218-1000\Control Panel\International\Geo\Nation	DCRatBuild_actual.exe
Key value queried	\REGISTRY\USER\S-1-5-21-2437139445-1151884604-3026847218-1000\Control Panel\International\Geo\Nation	WScript.exe
Key value queried	\REGISTRY\USER\S-1-5-21-2437139445-1151884604-3026847218-1000\Control Panel\International\Geo\Nation	winSavessessionPerfcrtReviewdhcp.exe

Executes dropped EXE 4 IoCs

pid	Process
4112	AccurateBase 3.7.1.exe
3632	DCRatBuild_actual.exe
5044	winSavessessionPerfcrtReviewdhcp.exe
4844	taskhostw.exe

Adds Run key to start application 2 TTPs 5 IoCs

persistence

Registry Run Keys / Startup Folder

T1547.001

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\RuntimeBroker = "\"C:\\winSavessessionPerfcrt\\RuntimeBroker.exe\""	winSavessessionPerfcrtReviewdhcp.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\StartMenuExperienceHost = "\"C:\\Windows\\SystemApps\\Microsoft.Windows.StartMenuExperienceHost_cw5n1h2txyewy\\resources\\StartMenuExperienceHost.exe\""	winSavessessionPerfcrtReviewdhcp.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\taskhostw = "\"C:\\Windows\\System32\\MdSched\\taskhostw.exe\""	winSavessessionPerfcrtReviewdhcp.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\smss = "\"C:\\winSavessessionPerfcrt\\smss.exe\""	winSavessessionPerfcrtReviewdhcp.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\OfficeClickToRun = "\"C:\\winSavessessionPerfcrt\\OfficeClickToRun.exe\""	winSavessessionPerfcrtReviewdhcp.exe

Drops file in System32 directory 3 IoCs

description	ioc	Process
File created	C:\Windows\System32\MdSched\taskhostw.exe	winSavessessionPerfcrtReviewdhcp.exe
File opened for modification	C:\Windows\System32\MdSched\taskhostw.exe	winSavessessionPerfcrtReviewdhcp.exe
File created	C:\Windows\System32\MdSched\ea9f0e6c9e2dcd4dfacdaf29ba21541fb815a988	winSavessessionPerfcrtReviewdhcp.exe

Suspicious use of NtSetInformationThreadHideFromDebugger 1 IoCs

pid	Process
4112	AccurateBase 3.7.1.exe

Drops file in Windows directory 2 IoCs

description	ioc	Process
File created	C:\Windows\SystemApps\Microsoft.Windows.StartMenuExperienceHost_cw5n1h2txyewy\resources\StartMenuExperienceHost.exe	winSavessessionPerfcrtReviewdhcp.exe
File created	C:\Windows\SystemApps\Microsoft.Windows.StartMenuExperienceHost_cw5n1h2txyewy\resources\55b276f4edf653fe07efe8f1ecc32d3d195abd16	winSavessessionPerfcrtReviewdhcp.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 5 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_actual.exe
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	6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9bN.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	AccurateBase 3.7.1.exe

Modifies registry class 2 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-2437139445-1151884604-3026847218-1000_Classes\Local Settings	DCRatBuild_actual.exe
Key created	\REGISTRY\USER\S-1-5-21-2437139445-1151884604-3026847218-1000_Classes\Local Settings	winSavessessionPerfcrtReviewdhcp.exe

Scheduled Task/Job: Scheduled Task 1 TTPs 5 IoCs

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

persistence execution

Scheduled Task

T1053.005

pid	Process
3020	schtasks.exe
3376	schtasks.exe
1432	schtasks.exe
3204	schtasks.exe
648	schtasks.exe

Suspicious behavior: EnumeratesProcesses 5 IoCs

pid	Process
4112	AccurateBase 3.7.1.exe
4112	AccurateBase 3.7.1.exe
5044	winSavessessionPerfcrtReviewdhcp.exe
4844	taskhostw.exe
4844	taskhostw.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	5044	winSavessessionPerfcrtReviewdhcp.exe
Token: SeDebugPrivilege	4844	taskhostw.exe

Suspicious use of SetWindowsHookEx 3 IoCs

pid	Process
4112	AccurateBase 3.7.1.exe
4112	AccurateBase 3.7.1.exe
4112	AccurateBase 3.7.1.exe

Suspicious use of WriteProcessMemory 20 IoCs

description	pid	Process	procid_target
PID 3216 wrote to memory of 4112	3216	6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9bN.exe	83
PID 3216 wrote to memory of 4112	3216	6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9bN.exe	83
PID 3216 wrote to memory of 4112	3216	6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9bN.exe	83
PID 3216 wrote to memory of 3632	3216	6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9bN.exe	84
PID 3216 wrote to memory of 3632	3216	6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9bN.exe	84
PID 3216 wrote to memory of 3632	3216	6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9bN.exe	84
PID 3632 wrote to memory of 544	3632	DCRatBuild_actual.exe	85
PID 3632 wrote to memory of 544	3632	DCRatBuild_actual.exe	85
PID 3632 wrote to memory of 544	3632	DCRatBuild_actual.exe	85
PID 544 wrote to memory of 3272	544	WScript.exe	94
PID 544 wrote to memory of 3272	544	WScript.exe	94
PID 544 wrote to memory of 3272	544	WScript.exe	94
PID 3272 wrote to memory of 5044	3272	cmd.exe	96
PID 3272 wrote to memory of 5044	3272	cmd.exe	96
PID 5044 wrote to memory of 3648	5044	winSavessessionPerfcrtReviewdhcp.exe	102
PID 5044 wrote to memory of 3648	5044	winSavessessionPerfcrtReviewdhcp.exe	102
PID 3648 wrote to memory of 2516	3648	cmd.exe	104
PID 3648 wrote to memory of 2516	3648	cmd.exe	104
PID 3648 wrote to memory of 4844	3648	cmd.exe	112
PID 3648 wrote to memory of 4844	3648	cmd.exe	112

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\6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9bN.exe
"C:\Users\Admin\AppData\Local\Temp\6bf4772cae624456cb29b1201ed435eff4c925b27b48de326946b997d1098b9bN.exe"
1⤵
- Checks computer location settings
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:3216
- C:\Users\Admin\AppData\Roaming\AccurateBase 3.7.1.exe
  "C:\Users\Admin\AppData\Roaming\AccurateBase 3.7.1.exe"
  2⤵
  - Executes dropped EXE
  - Suspicious use of NtSetInformationThreadHideFromDebugger
  - System Location Discovery: System Language Discovery
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of SetWindowsHookEx
  PID:4112
- C:\Users\Admin\AppData\Roaming\DCRatBuild_actual.exe
  "C:\Users\Admin\AppData\Roaming\DCRatBuild_actual.exe"
  2⤵
  - Checks computer location settings
  - Executes dropped EXE
  - System Location Discovery: System Language Discovery
  - Modifies registry class
  - Suspicious use of WriteProcessMemory
  PID:3632
- - C:\Windows\SysWOW64\WScript.exe
    "C:\Windows\System32\WScript.exe" "C:\winSavessessionPerfcrt\AzPIsnzPQMcnb9MIj8ZxuK2AQR.vbe"
    3⤵
    - Checks computer location settings
    - System Location Discovery: System Language Discovery
    - Suspicious use of WriteProcessMemory
    PID:544
  - - C:\Windows\SysWOW64\cmd.exe
      C:\Windows\system32\cmd.exe /c ""C:\winSavessessionPerfcrt\FPa26672dC5vdA2uBv5IhhyTUv2Yu.bat" "
      4⤵
      System Location Discovery: System Language Discovery
      Suspicious use of WriteProcessMemory
      PID:3272
    - - C:\winSavessessionPerfcrt\winSavessessionPerfcrtReviewdhcp.exe
        
        "C:\winSavessessionPerfcrt\winSavessessionPerfcrtReviewdhcp.exe"
        5⤵
        Checks computer location settings
        Executes dropped EXE
        Adds Run key to start application
        Drops file in System32 directory
        Drops file in Windows directory
        Modifies registry class
        Suspicious behavior: EnumeratesProcesses
        Suspicious use of AdjustPrivilegeToken
        Suspicious use of WriteProcessMemory
        
        PID:5044
      - C:\Windows\System32\cmd.exe
        
        "C:\Windows\System32\cmd.exe" /C "C:\Users\Admin\AppData\Local\Temp\bBZ4PJ5JB3.bat"
        6⤵
        Suspicious use of WriteProcessMemory
        
        PID:3648
        
        C:\Windows\system32\w32tm.exe
        
        w32tm /stripchart /computer:localhost /period:5 /dataonly /samples:2
        7⤵
        
        PID:2516
        
        C:\Windows\System32\MdSched\taskhostw.exe
        
        "C:\Windows\System32\MdSched\taskhostw.exe"
        7⤵
        Drops file in Drivers directory
        Executes dropped EXE
        Suspicious behavior: EnumeratesProcesses
        Suspicious use of AdjustPrivilegeToken
        
        PID:4844

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "taskhostw" /sc ONLOGON /tr "'C:\Windows\System32\MdSched\taskhostw.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:648

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "smss" /sc ONLOGON /tr "'C:\winSavessessionPerfcrt\smss.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:3020

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "OfficeClickToRun" /sc ONLOGON /tr "'C:\winSavessessionPerfcrt\OfficeClickToRun.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:3376

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "RuntimeBroker" /sc ONLOGON /tr "'C:\winSavessessionPerfcrt\RuntimeBroker.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:1432

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "StartMenuExperienceHost" /sc ONLOGON /tr "'C:\Windows\SystemApps\Microsoft.Windows.StartMenuExperienceHost_cw5n1h2txyewy\resources\StartMenuExperienceHost.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:3204

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

1

T1547

Registry Run Keys / Startup Folder

1

T1547.001

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Privilege Escalation

Boot or Logon Autostart Execution

1

T1547

Registry Run Keys / Startup Folder

1

T1547.001

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Defense Evasion

Modify Registry

1

T1112

Credential Access

Discovery

Query Registry

2

T1012

System Information Discovery

2

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:\Users\Admin\AppData\Local\Temp\bBZ4PJ5JB3.bat

Filesize
205B

MD5
5eadb3d5195c8548c116ea2a1cd08785

SHA1
e2de7225026d6f4e37043147cdbc825e9773010b

SHA256
0d521b314555cc71ed170fb2bcc258978e310f8d84aa279530196bc2fcb10071

SHA512
2843ecde75bff8a24991863a4a66dca8a0170e68e6f1d298ffba3574e3738556f72dc68a7107e9c77972a19a69d3af3b1df40e094c5de348444d548f0d4798d8

Download Submit
C:\Users\Admin\AppData\Roaming\AccurateBase 3.7.1.exe

Filesize
6.3MB

MD5
4dfb8e6353a95274e54ce6930cdd9a01

SHA1
23469c142723afd6a6287bb80013a37076bd6fcc

SHA256
e49d072f7c6f476ff8a7f63c153d34343ba8730f229de6306d7a788ed21720b7

SHA512
f7840137cb4569851b44fe3f6c3fc0c2fc37df6ef6b22310e73e2cfe4a3fa04b7d5aa58fc94ea1b2165b50ca83acca97142fd282251ae4502e727e7bb4102eb9

Download Submit
C:\Users\Admin\AppData\Roaming\DCRatBuild_actual.exe

Filesize
2.6MB

MD5
5d3db3851e7e001e7996a01366e70f15

SHA1
6a3204b2ca4df896d3ee8ca6bfb80bf55a7f24ff

SHA256
6d9ec01b5fc9aedcb4352f41667230043e1e4575d5e1cf47bfa0a4f0fed71e15

SHA512
55bce3cda4c7d8216fbf724228dd55dbe1acfebaa8890755dd30c3fda4c33f7c9bff19618702f994f98858bf0260c29ff330f7c87a5c01ad0b14108620552ab7

Download Submit
C:\winSavessessionPerfcrt\AzPIsnzPQMcnb9MIj8ZxuK2AQR.vbe

Filesize
229B

MD5
5ce2f4a68ccb9a203c0a5c4b38ed5a02

SHA1
fbc0ee263d0b62dfbe23dff0807571f7a7077594

SHA256
982849ce4f817a075be7131286e93a6b57aae9741d0adaca77cd141857e25339

SHA512
0f55605b72a4d6333fd01f9c313bb6fdccc4191809a86d374fdd1d6bb789cbcff498e77dd44f7ae2e82eeff3e1df8078394ddf5efd82b1fafdad73d21bfe1d8b

Download Submit
C:\winSavessessionPerfcrt\FPa26672dC5vdA2uBv5IhhyTUv2Yu.bat

Filesize
64B

MD5
dbdd562f39890812c24256bd82dacd5c

SHA1
d48c5fd83f28582c334308508b6b3e8285e70e92

SHA256
36c3dbb723975dfa8d756cdcc8d08d5bf0656bc4e7f1045bfa4a019ea5ba1472

SHA512
47910fa4d53321687b764d487535952dec578e336beaf2b6ee39c505a13d25e05465972c9ec391ac8e810520cf26c77ff2c1f7b7a8ffd9e766c2fbc1778dcd08

Download Submit
C:\winSavessessionPerfcrt\winSavessessionPerfcrtReviewdhcp.exe

Filesize
2.3MB

MD5
0108d4c7b51acb6ed7010e822df3bed4

SHA1
cea61376626d0d7cf92a1db625262ef611e6dfbe

SHA256
8f919979d62dc7d278a89c20a73367c97629ce89219c55052383b1df36a88e4e

SHA512
eb192434f234326fe2c75c89b010474c69eb9bfc77c9a1d37b6471e27e0ff58ec694560b38ba1f0595be74b372a9cd5e0bc174740074c463b0f8cf4bbc26a4b4

Download Submit
memory/4112-20-0x00000000007D3000-0x00000000007D8000-memory.dmp

Filesize
20KB

Download
memory/4112-34-0x0000000000400000-0x00000000014BB000-memory.dmp

Filesize
16.7MB

Download
memory/4112-35-0x0000000000400000-0x00000000014BB000-memory.dmp

Filesize
16.7MB

Download
memory/4112-33-0x0000000000400000-0x00000000014BB000-memory.dmp

Filesize
16.7MB

Download
memory/4112-22-0x0000000000400000-0x00000000014BB000-memory.dmp

Filesize
16.7MB

Download
memory/4112-57-0x0000000000400000-0x00000000014BB000-memory.dmp

Filesize
16.7MB

Download
memory/4112-16-0x0000000000400000-0x00000000014BB000-memory.dmp

Filesize
16.7MB

Download
memory/4844-61-0x0000000002930000-0x0000000002938000-memory.dmp

Filesize
32KB

Download
memory/4844-71-0x00000000029E0000-0x00000000029EA000-memory.dmp

Filesize
40KB

Download
memory/4844-62-0x0000000002940000-0x0000000002948000-memory.dmp

Filesize
32KB

Download
memory/4844-63-0x0000000002970000-0x0000000002978000-memory.dmp

Filesize
32KB

Download
memory/4844-65-0x0000000002980000-0x000000000298C000-memory.dmp

Filesize
48KB

Download
memory/4844-66-0x0000000002990000-0x000000000299C000-memory.dmp

Filesize
48KB

Download
memory/4844-67-0x00000000029B0000-0x00000000029B8000-memory.dmp

Filesize
32KB

Download
memory/4844-76-0x000000001B870000-0x000000001B8C6000-memory.dmp

Filesize
344KB

Download
memory/4844-72-0x0000000002A00000-0x0000000002A0E000-memory.dmp

Filesize
56KB

Download
memory/4844-70-0x00000000029A0000-0x00000000029A8000-memory.dmp

Filesize
32KB

Download
memory/4844-73-0x00000000029F0000-0x00000000029FC000-memory.dmp

Filesize
48KB

Download
memory/4844-75-0x0000000002A20000-0x0000000002A2C000-memory.dmp

Filesize
48KB

Download
memory/4844-74-0x0000000002A10000-0x0000000002A18000-memory.dmp

Filesize
32KB

Download
memory/4844-69-0x00000000029D0000-0x00000000029DA000-memory.dmp

Filesize
40KB

Download
memory/4844-68-0x00000000029C0000-0x00000000029C8000-memory.dmp

Filesize
32KB

Download
memory/5044-40-0x0000000000BA0000-0x0000000000DE8000-memory.dmp

Filesize
2.3MB

Download

Analysis

Sharing

General

Malware Config

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

Replay Monitor

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Downloads