dcrat | e4ddc55ae7aa7e087eadaa449eeed1a7de253565f7b2ef53c2e9bfec5d55dcfc

General

Target

e4ddc55ae7aa7e087eadaa449eeed1a7de253565f7b2ef53c2e9bfec5d55dcfc.exe
Size

1.4MB
MD5

0745161ebca7b94e13caca7a0f89b7fb
SHA1

9dfb820c738616a08042081cda0c4dcbdbb4a970
SHA256

e4ddc55ae7aa7e087eadaa449eeed1a7de253565f7b2ef53c2e9bfec5d55dcfc
SHA512

d7bfe29f1e5a73c1dc8e31d148dd4e62265f5d7a3897061cba9d63bfa6541cab77aabfb17f89c090092f980f132a55f7eab5e6da99a2eece21afde3db02a67be
SSDEEP

24576:z2G/nvxW3WwL+zdHJ2zljtfM8zCxqY3+SiSals+S5WhqN7+4H:zbA3f+hp4Zle+SIqNqo

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	3692	3220	schtasks.exe	87
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	4476	3220	schtasks.exe	87
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2628	3220	schtasks.exe	87
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2780	3220	schtasks.exe	87
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	4832	3220	schtasks.exe	87

DCRat payload 2 IoCs

Detects payload of DCRat, commonly dropped by NSIS installers.

rat

resource	yara_rule
behavioral2/files/0x000a000000023b8b-9.dat	dcrat
behavioral2/memory/4004-13-0x0000000000100000-0x000000000021E000-memory.dmp	dcrat

Checks computer location settings 2 TTPs 3 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-1-5-21-3350944739-639801879-157714471-1000\Control Panel\International\Geo\Nation	e4ddc55ae7aa7e087eadaa449eeed1a7de253565f7b2ef53c2e9bfec5d55dcfc.exe
Key value queried	\REGISTRY\USER\S-1-5-21-3350944739-639801879-157714471-1000\Control Panel\International\Geo\Nation	WScript.exe
Key value queried	\REGISTRY\USER\S-1-5-21-3350944739-639801879-157714471-1000\Control Panel\International\Geo\Nation	ReviewsessionbrokerdllBrokerhostNet.exe

Executes dropped EXE 2 IoCs

pid	Process
4004	ReviewsessionbrokerdllBrokerhostNet.exe
4176	RuntimeBroker.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\services = "\"C:\\Documents and Settings\\services.exe\""	ReviewsessionbrokerdllBrokerhostNet.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\RuntimeBroker = "\"C:\\Windows\\System32\\prnfldr\\RuntimeBroker.exe\""	ReviewsessionbrokerdllBrokerhostNet.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\sihost = "\"C:\\Reviewsessionbrokerdll\\sihost.exe\""	ReviewsessionbrokerdllBrokerhostNet.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\lsass = "\"C:\\Windows\\System32\\cttune\\lsass.exe\""	ReviewsessionbrokerdllBrokerhostNet.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\csrss = "\"C:\\Program Files (x86)\\Internet Explorer\\images\\csrss.exe\""	ReviewsessionbrokerdllBrokerhostNet.exe

Drops file in System32 directory 4 IoCs

description	ioc	Process
File created	C:\Windows\System32\prnfldr\9e8d7a4ca61bd92aff00cc37a7a4d62a2cac998d	ReviewsessionbrokerdllBrokerhostNet.exe
File created	C:\Windows\System32\cttune\lsass.exe	ReviewsessionbrokerdllBrokerhostNet.exe
File created	C:\Windows\System32\cttune\6203df4a6bafc7c328ee7f6f8ca0a8a838a8a1b9	ReviewsessionbrokerdllBrokerhostNet.exe
File created	C:\Windows\System32\prnfldr\RuntimeBroker.exe	ReviewsessionbrokerdllBrokerhostNet.exe

Drops file in Program Files directory 2 IoCs

description	ioc	Process
File created	C:\Program Files (x86)\Internet Explorer\images\csrss.exe	ReviewsessionbrokerdllBrokerhostNet.exe
File created	C:\Program Files (x86)\Internet Explorer\images\886983d96e3d3e31032c679b2d4ea91b6c05afef	ReviewsessionbrokerdllBrokerhostNet.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	e4ddc55ae7aa7e087eadaa449eeed1a7de253565f7b2ef53c2e9bfec5d55dcfc.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	WScript.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe

Modifies registry class 1 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-3350944739-639801879-157714471-1000_Classes\Local Settings	e4ddc55ae7aa7e087eadaa449eeed1a7de253565f7b2ef53c2e9bfec5d55dcfc.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
4832	schtasks.exe
3692	schtasks.exe
4476	schtasks.exe
2628	schtasks.exe
2780	schtasks.exe

Suspicious behavior: EnumeratesProcesses 3 IoCs

pid	Process
4004	ReviewsessionbrokerdllBrokerhostNet.exe
4176	RuntimeBroker.exe
4176	RuntimeBroker.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	4004	ReviewsessionbrokerdllBrokerhostNet.exe
Token: SeDebugPrivilege	4176	RuntimeBroker.exe

Suspicious use of WriteProcessMemory 10 IoCs

description	pid	Process	procid_target
PID 2212 wrote to memory of 1608	2212	e4ddc55ae7aa7e087eadaa449eeed1a7de253565f7b2ef53c2e9bfec5d55dcfc.exe	83
PID 2212 wrote to memory of 1608	2212	e4ddc55ae7aa7e087eadaa449eeed1a7de253565f7b2ef53c2e9bfec5d55dcfc.exe	83
PID 2212 wrote to memory of 1608	2212	e4ddc55ae7aa7e087eadaa449eeed1a7de253565f7b2ef53c2e9bfec5d55dcfc.exe	83
PID 1608 wrote to memory of 2584	1608	WScript.exe	84
PID 1608 wrote to memory of 2584	1608	WScript.exe	84
PID 1608 wrote to memory of 2584	1608	WScript.exe	84
PID 2584 wrote to memory of 4004	2584	cmd.exe	86
PID 2584 wrote to memory of 4004	2584	cmd.exe	86
PID 4004 wrote to memory of 4176	4004	ReviewsessionbrokerdllBrokerhostNet.exe	93
PID 4004 wrote to memory of 4176	4004	ReviewsessionbrokerdllBrokerhostNet.exe	93

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\e4ddc55ae7aa7e087eadaa449eeed1a7de253565f7b2ef53c2e9bfec5d55dcfc.exe
"C:\Users\Admin\AppData\Local\Temp\e4ddc55ae7aa7e087eadaa449eeed1a7de253565f7b2ef53c2e9bfec5d55dcfc.exe"
1⤵
- Checks computer location settings
- System Location Discovery: System Language Discovery
- Modifies registry class
- Suspicious use of WriteProcessMemory
PID:2212
- C:\Windows\SysWOW64\WScript.exe
  "C:\Windows\System32\WScript.exe" "C:\Reviewsessionbrokerdll\lVMLXJBAdPIapT.vbe"
  2⤵
  - Checks computer location settings
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:1608
- - C:\Windows\SysWOW64\cmd.exe
    C:\Windows\system32\cmd.exe /c ""C:\Reviewsessionbrokerdll\A6Eco3zU0RirI70.bat" "
    3⤵
    - System Location Discovery: System Language Discovery
    - Suspicious use of WriteProcessMemory
    PID:2584
  - - C:\Reviewsessionbrokerdll\ReviewsessionbrokerdllBrokerhostNet.exe
      "C:\Reviewsessionbrokerdll\ReviewsessionbrokerdllBrokerhostNet.exe"
      4⤵
      Checks computer location settings
      Executes dropped EXE
      Adds Run key to start application
      Drops file in System32 directory
      Drops file in Program Files directory
      Suspicious behavior: EnumeratesProcesses
      Suspicious use of AdjustPrivilegeToken
      Suspicious use of WriteProcessMemory
      PID:4004
    - - C:\Windows\System32\prnfldr\RuntimeBroker.exe
        
        "C:\Windows\System32\prnfldr\RuntimeBroker.exe"
        5⤵
        Executes dropped EXE
        Suspicious behavior: EnumeratesProcesses
        Suspicious use of AdjustPrivilegeToken
        
        PID:4176

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "services" /sc ONLOGON /tr "'C:\Documents and Settings\services.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:3692

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "RuntimeBroker" /sc ONLOGON /tr "'C:\Windows\System32\prnfldr\RuntimeBroker.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:4476

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "sihost" /sc ONLOGON /tr "'C:\Reviewsessionbrokerdll\sihost.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2628

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "lsass" /sc ONLOGON /tr "'C:\Windows\System32\cttune\lsass.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:2780

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "csrss" /sc ONLOGON /tr "'C:\Program Files (x86)\Internet Explorer\images\csrss.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Scheduled Task/Job: Scheduled Task
PID:4832

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:\Reviewsessionbrokerdll\A6Eco3zU0RirI70.bat

Filesize
67B

MD5
88c29e093073e22265a1b092448f78ff

SHA1
7562a360c1ec30c93f3897fef165265e9b83c641

SHA256
1c948ec9ca40c8a579471b1a7353c3c06cb4c961993962304fb0f60cfaee7333

SHA512
51447ebfe6eaa496eb449bf8ff5184389a6d89ed36042e8916663587e1e0a2b563e8a977adab3d1e7c6c32d7d74eb0b1c7ee21d68b68202d114d877269a76f1e

Download Submit
C:\Reviewsessionbrokerdll\ReviewsessionbrokerdllBrokerhostNet.exe

Filesize
1.1MB

MD5
1612f102a43924196f6c67852264eee8

SHA1
49b0ca8d344345a84622d020b1b8d4057ab02868

SHA256
cd7d786f6ffe4622aad7f8f7bba9de05c09cf37ed9a4c21a398e92808bd13d35

SHA512
f32d5d110ac8c1356a70fe204c9e12663db2df4f35943532d81b277d597b28da92ec8550957479cb1a070564e8518839469a2a2dac4477b60fa1a203e5b371d4

Download Submit
C:\Reviewsessionbrokerdll\lVMLXJBAdPIapT.vbe

Filesize
214B

MD5
f3e2d57473806af2657d0ecc4d9776cb

SHA1
8d215aef321e642586cbdf25d251b60a42aa41c3

SHA256
e05139fb41a25ef9796b27b604fb54b27394e5f5b33874d4b15445d9de2fbcca

SHA512
0d7b22cc29c82c175309ea5da45ce6f159022cc45e21f950add7ce24b3cde62c74b4eb598300bab1e1244fb8a963be29388baa2f6333033fd0dce6c3fcca04db

Download Submit
memory/4004-12-0x00007FFCC1863000-0x00007FFCC1865000-memory.dmp

Filesize
8KB

Download
memory/4004-13-0x0000000000100000-0x000000000021E000-memory.dmp

Filesize
1.1MB

Download
memory/4176-36-0x000000001BF00000-0x000000001BF0A000-memory.dmp

Filesize
40KB

Download
memory/4176-35-0x000000001B9F0000-0x000000001B9F8000-memory.dmp

Filesize
32KB

Download
memory/4176-37-0x000000001BE10000-0x000000001BE1C000-memory.dmp

Filesize
48KB

Download
memory/4176-38-0x000000001BE20000-0x000000001BE2E000-memory.dmp

Filesize
56KB

Download
memory/4176-39-0x000000001BE00000-0x000000001BE08000-memory.dmp

Filesize
32KB

Download
memory/4176-41-0x000000001BE40000-0x000000001BE48000-memory.dmp

Filesize
32KB

Download
memory/4176-40-0x000000001BE30000-0x000000001BE38000-memory.dmp

Filesize
32KB

Download
memory/4176-43-0x000000001BEA0000-0x000000001BEA8000-memory.dmp

Filesize
32KB

Download
memory/4176-42-0x000000001BE60000-0x000000001BE68000-memory.dmp

Filesize
32KB

Download

Analysis

Sharing

General

Malware Config

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads