dcrat | 0c70ff796c9a6c8e20437dcd29e1be3951ac7dae8bc0e75bbbae5b710c6be70e

General

Target

a77873bfea27896f94731478d64541a3.exe
Size

873KB
MD5

a77873bfea27896f94731478d64541a3
SHA1

9d9596b12d51e06dd1c509c3df0cb7432fb60156
SHA256

0c70ff796c9a6c8e20437dcd29e1be3951ac7dae8bc0e75bbbae5b710c6be70e
SHA512

34c94a9e432bb0d4e2154ca80d2a42bb47e4a3ff29a5ecb9d24eb4db235a3dfb7e6c532edb05bcb4a1e299c4b040e39d2c0eeeac8593e7b0babcdaf834e49a0e

Score

10^/10

dcrat infostealer persistence rat

Malware Config

Signatures

DcRat 11 IoCs

DarkCrystal(DC) is a new .NET RAT active since June 2019 capable of loading additional plugins.

rat infostealer dcrat

Processes:

a77873bfea27896f94731478d64541a3.exeschtasks.exeschtasks.exeschtasks.exeschtasks.exeschtasks.exeschtasks.exeschtasks.exe

description	ioc	process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\services = "\"C:\\Users\\Public\\services.exe\""	a77873bfea27896f94731478d64541a3.exe
3200	schtasks.exe
File created	C:\Program Files\Microsoft Office\Updates\Download\PackageFiles\MoUsoCoreWorker.exe	a77873bfea27896f94731478d64541a3.exe
3252	schtasks.exe
2692	schtasks.exe
3276	schtasks.exe
916	schtasks.exe
776	schtasks.exe
3300	schtasks.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\MoUsoCoreWorker = "\"C:\\Program Files\\Microsoft Office\\Updates\\Download\\PackageFiles\\MoUsoCoreWorker.exe\""	a77873bfea27896f94731478d64541a3.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\fontdrvhost = "\"C:\\PerfLogs\\fontdrvhost.exe\""	a77873bfea27896f94731478d64541a3.exe

Process spawned unexpected child process 7 IoCs

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

Processes:

schtasks.exeschtasks.exeschtasks.exeschtasks.exeschtasks.exeschtasks.exeschtasks.exe

description	pid	pid_target	process
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	3276	3652	schtasks.exe
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	916	3652	schtasks.exe
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	3200	3652	schtasks.exe
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	776	3652	schtasks.exe
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	3252	3652	schtasks.exe
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	3300	3652	schtasks.exe
Parent C:\Windows\system32\wbem\wmiprvse.exe is not expected to spawn this process	2692	3652	schtasks.exe

Executes dropped EXE 1 IoCs

Processes:

MoUsoCoreWorker.exe

pid process

1580 MoUsoCoreWorker.exe

pid	process
1580	MoUsoCoreWorker.exe

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:

a77873bfea27896f94731478d64541a3.exe

description	ioc	process
Key value queried	\REGISTRY\USER\S-1-5-21-790714498-1549421491-1643397139-1000\Control Panel\International\Geo\Nation	a77873bfea27896f94731478d64541a3.exe

Adds Run key to start application 2 TTPs 7 IoCs

persistence

Registry Run Keys / Startup Folder

T1060

Modify Registry

T1112

Processes:

a77873bfea27896f94731478d64541a3.exe

description	ioc	process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\sihost = "\"C:\\Windows\\System32\\mspatcha\\sihost.exe\""	a77873bfea27896f94731478d64541a3.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\MoUsoCoreWorker = "\"C:\\Program Files\\Microsoft Office\\Updates\\Download\\PackageFiles\\MoUsoCoreWorker.exe\""	a77873bfea27896f94731478d64541a3.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\services = "\"C:\\Users\\Public\\services.exe\""	a77873bfea27896f94731478d64541a3.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\fontdrvhost = "\"C:\\PerfLogs\\fontdrvhost.exe\""	a77873bfea27896f94731478d64541a3.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\RuntimeBroker = "\"C:\\Windows\\System32\\mfcore\\RuntimeBroker.exe\""	a77873bfea27896f94731478d64541a3.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\lsass = "\"C:\\Windows\\System32\\MSPhotography\\lsass.exe\""	a77873bfea27896f94731478d64541a3.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\MoUsoCoreWorker = "\"C:\\Windows\\System32\\BthpanContextHandler\\MoUsoCoreWorker.exe\""	a77873bfea27896f94731478d64541a3.exe

Drops file in System32 directory 8 IoCs

Processes:

a77873bfea27896f94731478d64541a3.exe

description	ioc	process
File created	C:\Windows\System32\MSPhotography\lsass.exe	a77873bfea27896f94731478d64541a3.exe
File created	C:\Windows\System32\MSPhotography\6203df4a6bafc7	a77873bfea27896f94731478d64541a3.exe
File created	C:\Windows\System32\BthpanContextHandler\MoUsoCoreWorker.exe	a77873bfea27896f94731478d64541a3.exe
File created	C:\Windows\System32\BthpanContextHandler\1f93f77a7f4778	a77873bfea27896f94731478d64541a3.exe
File created	C:\Windows\System32\mspatcha\sihost.exe	a77873bfea27896f94731478d64541a3.exe
File created	C:\Windows\System32\mspatcha\66fc9ff0ee96c2	a77873bfea27896f94731478d64541a3.exe
File created	C:\Windows\System32\mfcore\RuntimeBroker.exe	a77873bfea27896f94731478d64541a3.exe
File created	C:\Windows\System32\mfcore\9e8d7a4ca61bd9	a77873bfea27896f94731478d64541a3.exe

Drops file in Program Files directory 3 IoCs

Processes:

a77873bfea27896f94731478d64541a3.exe

description	ioc	process
File created	C:\Program Files\Microsoft Office\Updates\Download\PackageFiles\MoUsoCoreWorker.exe	a77873bfea27896f94731478d64541a3.exe
File opened for modification	C:\Program Files\Microsoft Office\Updates\Download\PackageFiles\MoUsoCoreWorker.exe	a77873bfea27896f94731478d64541a3.exe
File created	C:\Program Files\Microsoft Office\Updates\Download\PackageFiles\1f93f77a7f4778	a77873bfea27896f94731478d64541a3.exe

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

System Information Discovery
T1082

Checks processor information in registry 2 TTPs 2 IoCs

Processor information is often read in order to detect sandboxing environments.

Query Registry

T1012

System Information Discovery

T1082

Processes:

MusNotifyIcon.exe

description	ioc	process
Key opened	\Registry\Machine\HARDWARE\DESCRIPTION\System\CentralProcessor\0	MusNotifyIcon.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\~MHz	MusNotifyIcon.exe

Creates scheduled task(s) 1 TTPs 7 IoCs
Schtasks is often used by malware for persistence or to perform post-infection execution.
persistence

Scheduled Task
T1053

Processes:

schtasks.exeschtasks.exeschtasks.exeschtasks.exeschtasks.exeschtasks.exeschtasks.exe

pid process

3276 schtasks.exe
916 schtasks.exe
3200 schtasks.exe
776 schtasks.exe
3252 schtasks.exe
3300 schtasks.exe
2692 schtasks.exe

pid	process
3276	schtasks.exe
916	schtasks.exe
3200	schtasks.exe
776	schtasks.exe
3252	schtasks.exe
3300	schtasks.exe
2692	schtasks.exe

Suspicious behavior: EnumeratesProcesses 11 IoCs

Processes:

a77873bfea27896f94731478d64541a3.exeMoUsoCoreWorker.exe

pid	process
984	a77873bfea27896f94731478d64541a3.exe
984	a77873bfea27896f94731478d64541a3.exe
984	a77873bfea27896f94731478d64541a3.exe
984	a77873bfea27896f94731478d64541a3.exe
984	a77873bfea27896f94731478d64541a3.exe
984	a77873bfea27896f94731478d64541a3.exe
984	a77873bfea27896f94731478d64541a3.exe
1580	MoUsoCoreWorker.exe
1580	MoUsoCoreWorker.exe
1580	MoUsoCoreWorker.exe
1580	MoUsoCoreWorker.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

Processes:

a77873bfea27896f94731478d64541a3.exeMoUsoCoreWorker.exe

description pid process

Token: SeDebugPrivilege 984 a77873bfea27896f94731478d64541a3.exe
Token: SeDebugPrivilege 1580 MoUsoCoreWorker.exe

description	pid	process
Token: SeDebugPrivilege	984	a77873bfea27896f94731478d64541a3.exe
Token: SeDebugPrivilege	1580	MoUsoCoreWorker.exe

Suspicious use of WriteProcessMemory 2 IoCs

Processes:

a77873bfea27896f94731478d64541a3.exe

description	pid	process	target process
PID 984 wrote to memory of 1580	984	a77873bfea27896f94731478d64541a3.exe	MoUsoCoreWorker.exe
PID 984 wrote to memory of 1580	984	a77873bfea27896f94731478d64541a3.exe	MoUsoCoreWorker.exe

C:\Users\Admin\AppData\Local\Temp\a77873bfea27896f94731478d64541a3.exe
"C:\Users\Admin\AppData\Local\Temp\a77873bfea27896f94731478d64541a3.exe"
1⤵
- DcRat
- Checks computer location settings
- 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:984

C:\Program Files\Microsoft Office\Updates\Download\PackageFiles\MoUsoCoreWorker.exe
"C:\Program Files\Microsoft Office\Updates\Download\PackageFiles\MoUsoCoreWorker.exe"
2⤵
- Executes dropped EXE
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
PID:1580

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "MoUsoCoreWorker" /sc ONLOGON /tr "'C:\Program Files\Microsoft Office\Updates\Download\PackageFiles\MoUsoCoreWorker.exe'" /rl HIGHEST /f
1⤵
- DcRat
- Process spawned unexpected child process
- Creates scheduled task(s)
PID:3276

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "services" /sc ONLOGON /tr "'C:\Users\Public\services.exe'" /rl HIGHEST /f
1⤵
- DcRat
- Process spawned unexpected child process
- Creates scheduled task(s)
PID:916

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "fontdrvhost" /sc ONLOGON /tr "'C:\PerfLogs\fontdrvhost.exe'" /rl HIGHEST /f
1⤵
- DcRat
- Process spawned unexpected child process
- Creates scheduled task(s)
PID:3200

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "RuntimeBroker" /sc ONLOGON /tr "'C:\Windows\System32\mfcore\RuntimeBroker.exe'" /rl HIGHEST /f
1⤵
- DcRat
- Process spawned unexpected child process
- Creates scheduled task(s)
PID:776

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "lsass" /sc ONLOGON /tr "'C:\Windows\System32\MSPhotography\lsass.exe'" /rl HIGHEST /f
1⤵
- DcRat
- Process spawned unexpected child process
- Creates scheduled task(s)
PID:3252

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "MoUsoCoreWorker" /sc ONLOGON /tr "'C:\Windows\System32\BthpanContextHandler\MoUsoCoreWorker.exe'" /rl HIGHEST /f
1⤵
- DcRat
- Process spawned unexpected child process
- Creates scheduled task(s)
PID:3300

C:\Windows\system32\schtasks.exe
schtasks.exe /create /tn "sihost" /sc ONLOGON /tr "'C:\Windows\System32\mspatcha\sihost.exe'" /rl HIGHEST /f
1⤵
- DcRat
- Process spawned unexpected child process
- Creates scheduled task(s)
PID:2692

C:\Windows\system32\MusNotifyIcon.exe
%systemroot%\system32\MusNotifyIcon.exe NotifyTrayIcon 13
1⤵
- Checks processor information in registry
PID:760

C:\Windows\System32\svchost.exe
C:\Windows\System32\svchost.exe -k NetworkService -p
1⤵
PID:2432

Network

MITRE ATT&CK Matrix ATT&CK v6

Initial Access

Execution

Scheduled Task

1

T1053

Persistence

Registry Run Keys / Startup Folder

1

T1060

Scheduled Task

1

T1053

Privilege Escalation

Scheduled Task

1

T1053

Defense Evasion

Modify Registry

1

T1112

Credential Access

Discovery

Query Registry

2

T1012

System Information Discovery

3

T1082

Lateral Movement

Collection

Exfiltration

Command and Control

Impact

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Downloads

C:\Program Files\Microsoft Office\Updates\Download\PackageFiles\MoUsoCoreWorker.exe
MD5
a77873bfea27896f94731478d64541a3

SHA1
9d9596b12d51e06dd1c509c3df0cb7432fb60156

SHA256
0c70ff796c9a6c8e20437dcd29e1be3951ac7dae8bc0e75bbbae5b710c6be70e

SHA512
34c94a9e432bb0d4e2154ca80d2a42bb47e4a3ff29a5ecb9d24eb4db235a3dfb7e6c532edb05bcb4a1e299c4b040e39d2c0eeeac8593e7b0babcdaf834e49a0e

Download Submit
C:\Program Files\Microsoft Office\Updates\Download\PackageFiles\MoUsoCoreWorker.exe
MD5
a77873bfea27896f94731478d64541a3

SHA1
9d9596b12d51e06dd1c509c3df0cb7432fb60156

SHA256
0c70ff796c9a6c8e20437dcd29e1be3951ac7dae8bc0e75bbbae5b710c6be70e

SHA512
34c94a9e432bb0d4e2154ca80d2a42bb47e4a3ff29a5ecb9d24eb4db235a3dfb7e6c532edb05bcb4a1e299c4b040e39d2c0eeeac8593e7b0babcdaf834e49a0e

Download Submit
memory/984-130-0x00007FFB34D53000-0x00007FFB34D55000-memory.dmp

Filesize
8KB

Download
memory/984-131-0x00000000003A0000-0x0000000000482000-memory.dmp

Filesize
904KB

Download
memory/984-132-0x0000000002440000-0x0000000002442000-memory.dmp

Filesize
8KB

Download
memory/1580-135-0x00007FFB34D53000-0x00007FFB34D55000-memory.dmp

Filesize
8KB

Download
memory/1580-136-0x000000001D090000-0x000000001D092000-memory.dmp

Filesize
8KB

Download

Analysis

Sharing

General

Malware Config

Signatures

Processes

Network

MITRE ATT&CK Matrix ATT&CK v6

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Downloads