dcrat | 48a5d085cf6540b1dc286bbaa17141d6c40d3aa37a6a92c6326873ca98f25e8a

General

Target

HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe
Size

1.1MB
MD5

89eafa0c3e68136ae780afb0bed528be
SHA1

8c80cb2d82eabc6a9d6bc582c0a4c67b4bc79bc3
SHA256

48a5d085cf6540b1dc286bbaa17141d6c40d3aa37a6a92c6326873ca98f25e8a
SHA512

e6a5a6a0602b3bb51235fee1a0a39a32327a62892635e1df7c0bc3135089718bac96ad878dabd6c8d35738a3a6595dabde716b6ebb78d17b75188b98de159e34
SSDEEP

12288:o8R51UropgKt6ljehIYulIB68SzlPqGlWVKZuMM2nwLjwkidihD9+HgMVeQqn4:X1UMb6ljehI7+6X+/WpHgeeQ+4

Score

10^/10

dcrat 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

Process spawned unexpected child process 4 IoCs

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

Processes:

schtasks.exeschtasks.exeschtasks.exeschtasks.exe

description	pid	pid_target	process
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	1580	4212	schtasks.exe
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	1804	4212	schtasks.exe
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	3828	4212	schtasks.exe
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	1556	4212	schtasks.exe

DCRat payload 4 IoCs

Detects payload of DCRat, commonly dropped by NSIS installers.

rat

Processes:

resource	yara_rule
behavioral2/memory/1320-133-0x0000000000E00000-0x0000000000F1A000-memory.dmp	dcrat
C:\PerfLogs\lsass.exe	dcrat
C:\PerfLogs\lsass.exe	dcrat
C:\PerfLogs\lsass.exe	dcrat

Checks computer location settings 2 TTPs 1 IoCs

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

Query Registry

T1012

System Information Discovery

T1082

Processes:

HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe

description	ioc	process
Key value queried	\REGISTRY\USER\S-1-5-21-1675742406-747946869-1029867430-1000\Control Panel\International\Geo\Nation	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe

Executes dropped EXE 1 IoCs

Processes:

lsass.exe

pid process

4888 lsass.exe

pid	process
4888	lsass.exe

Adds Run key to start application 2 TTPs 4 IoCs

persistence

Registry Run Keys / Startup Folder

T1060

Modify Registry

T1112

Processes:

HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe

description	ioc	process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\RuntimeBroker = "\"C:\\Recovery\\WindowsRE\\RuntimeBroker.exe\""	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\dwm = "\"C:\\Recovery\\WindowsRE\\dwm.exe\""	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\lsass = "\"C:\\PerfLogs\\lsass.exe\""	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\dllhost = "\"C:\\Program Files\\Internet Explorer\\ja-JP\\dllhost.exe\""	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe

Drops file in Program Files directory 3 IoCs

Processes:

HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe

description	ioc	process
File created	C:\Program Files\WindowsApps\Microsoft.WindowsCalculator_2020.1906.55.0_neutral_~_8wekyb3d8bbwe\microsoft.system.package.metadata\upfc.exe	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe
File created	C:\Program Files\Internet Explorer\ja-JP\dllhost.exe	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe
File created	C:\Program Files\Internet Explorer\ja-JP\5940a34987c99120d96dace90a3f93f329dcad63	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe

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

System Information Discovery
T1082
Creates scheduled task(s) 1 TTPs 4 IoCs
Schtasks is often used by malware for persistence or to perform post-infection execution.
persistence

Scheduled Task
T1053

Processes:

schtasks.exeschtasks.exeschtasks.exeschtasks.exe

pid process

1580 schtasks.exe
1804 schtasks.exe
3828 schtasks.exe
1556 schtasks.exe

pid	process
1580	schtasks.exe
1804	schtasks.exe
3828	schtasks.exe
1556	schtasks.exe

Modifies registry class 1 IoCs

Processes:

HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe

description	ioc	process
Key created	\REGISTRY\USER\S-1-5-21-1675742406-747946869-1029867430-1000_Classes\Local Settings	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe

Suspicious behavior: EnumeratesProcesses 2 IoCs

Processes:

HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exelsass.exe

pid process

1320 HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe
4888 lsass.exe
Suspicious use of AdjustPrivilegeToken 2 IoCs

Processes:

HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exelsass.exe

description pid process

Token: SeDebugPrivilege 1320 HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe
Token: SeDebugPrivilege 4888 lsass.exe

pid	process
1320	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe
4888	lsass.exe

description	pid	process
Token: SeDebugPrivilege	1320	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe
Token: SeDebugPrivilege	4888	lsass.exe

Suspicious use of WriteProcessMemory 8 IoCs

Processes:

HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.execmd.exe

description	pid	process	target process
PID 1320 wrote to memory of 4428	1320	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe	cmd.exe
PID 1320 wrote to memory of 4428	1320	HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe	cmd.exe
PID 4428 wrote to memory of 224	4428	cmd.exe	chcp.com
PID 4428 wrote to memory of 224	4428	cmd.exe	chcp.com
PID 4428 wrote to memory of 320	4428	cmd.exe	w32tm.exe
PID 4428 wrote to memory of 320	4428	cmd.exe	w32tm.exe
PID 4428 wrote to memory of 4888	4428	cmd.exe	lsass.exe
PID 4428 wrote to memory of 4888	4428	cmd.exe	lsass.exe

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\HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe
"C:\Users\Admin\AppData\Local\Temp\HEUR-Backdoor.MSIL.LightStone.gen-48a5d085cf6.exe"
1⤵
- Checks computer location settings
- Adds Run key to start application
- Drops file in Program Files directory
- Modifies registry class
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:1320

C:\Windows\System32\cmd.exe
"C:\Windows\System32\cmd.exe" /C "C:\Users\Admin\AppData\Local\Temp\5QvP45yfT9.bat"
2⤵
- Suspicious use of WriteProcessMemory
PID:4428

C:\Windows\system32\chcp.com
chcp 65001
3⤵
PID:224

C:\Windows\system32\w32tm.exe
w32tm /stripchart /computer:localhost /period:5 /dataonly /samples:2
3⤵
PID:320

C:\PerfLogs\lsass.exe
"C:\PerfLogs\lsass.exe"
3⤵
- Executes dropped EXE
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
PID:4888

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "RuntimeBroker" /sc ONLOGON /tr "'C:\Recovery\WindowsRE\RuntimeBroker.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Creates scheduled task(s)
PID:1580

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "dwm" /sc ONLOGON /tr "'C:\Recovery\WindowsRE\dwm.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Creates scheduled task(s)
PID:1804

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "lsass" /sc ONLOGON /tr "'C:\PerfLogs\lsass.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Creates scheduled task(s)
PID:3828

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "dllhost" /sc ONLOGON /tr "'C:\Program Files\Internet Explorer\ja-JP\dllhost.exe'" /rl HIGHEST /f
1⤵
- Process spawned unexpected child process
- Creates scheduled task(s)
PID:1556

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Scheduled Task

1

T1053

Persistence

Registry Run Keys / Startup Folder

Scheduled Task

Privilege Escalation

Scheduled Task

1

T1053

Defense Evasion

Modify Registry

1

T1112

Credential Access

Discovery

Query Registry

2

T1012

System Information Discovery

2

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

Replay Monitor

Loading Replay Monitor...

Downloads

C:\PerfLogs\lsass.exe
Filesize
1.1MB

MD5
89eafa0c3e68136ae780afb0bed528be

SHA1
8c80cb2d82eabc6a9d6bc582c0a4c67b4bc79bc3

SHA256
48a5d085cf6540b1dc286bbaa17141d6c40d3aa37a6a92c6326873ca98f25e8a

SHA512
e6a5a6a0602b3bb51235fee1a0a39a32327a62892635e1df7c0bc3135089718bac96ad878dabd6c8d35738a3a6595dabde716b6ebb78d17b75188b98de159e34

Download Submit
C:\PerfLogs\lsass.exe
Filesize
1.1MB

MD5
89eafa0c3e68136ae780afb0bed528be

SHA1
8c80cb2d82eabc6a9d6bc582c0a4c67b4bc79bc3

SHA256
48a5d085cf6540b1dc286bbaa17141d6c40d3aa37a6a92c6326873ca98f25e8a

SHA512
e6a5a6a0602b3bb51235fee1a0a39a32327a62892635e1df7c0bc3135089718bac96ad878dabd6c8d35738a3a6595dabde716b6ebb78d17b75188b98de159e34

Download Submit
C:\PerfLogs\lsass.exe
Filesize
1.1MB

MD5
89eafa0c3e68136ae780afb0bed528be

SHA1
8c80cb2d82eabc6a9d6bc582c0a4c67b4bc79bc3

SHA256
48a5d085cf6540b1dc286bbaa17141d6c40d3aa37a6a92c6326873ca98f25e8a

SHA512
e6a5a6a0602b3bb51235fee1a0a39a32327a62892635e1df7c0bc3135089718bac96ad878dabd6c8d35738a3a6595dabde716b6ebb78d17b75188b98de159e34

Download Submit
C:\Users\Admin\AppData\Local\Temp\5QvP45yfT9.bat
Filesize
197B

MD5
b923fe123947e0dca7fab3fd7dc460a8

SHA1
8d63b2c94db12826969a38407bc1785665cd6caa

SHA256
4c934c4acddaff7c477e9805931e2f8d4d7507173ae638808c5b700e806bf399

SHA512
563e99f4a609976857700af68398ccaedbd19247cd749aafe30367aaeaad014fb1bff63ee7549b832474443af64d27979f86112601d58a5573161afa73dde6f0

Download Submit
memory/1320-133-0x0000000000E00000-0x0000000000F1A000-memory.dmp

Filesize
1.1MB

Download
memory/1320-134-0x000000001BB20000-0x000000001BB30000-memory.dmp

Filesize
64KB

Download
memory/4888-153-0x000000001C300000-0x000000001C402000-memory.dmp

Filesize
1.0MB

Download

Analysis

Sharing

General

Malware Config

Signatures

Processes

Network

MITRE ATT&CK Enterprise v6

Replay Monitor

Loading Replay Monitor...

Downloads