tofsee | 54f74659a4f85bab878e448b3ae96242c24f98f054cd7a16ce2a6b6daae4a70e

General

Target

file.exe
Size

233KB
MD5

b76e2d8db8266762c770fbf801b33917
SHA1

f8a8d5ced370552210f2b449ec2822c48e470bac
SHA256

54f74659a4f85bab878e448b3ae96242c24f98f054cd7a16ce2a6b6daae4a70e
SHA512

55b1de5e83d1f2cb7840b2eee2ac40dfcb0c1d289568b63a41e4b459f5fbb599c934df2805c1dd9b2b344133a39d4c2950997796605624ffff4dac1b32d7f76b
SSDEEP

3072:EpqwYirEGOie1jXG7NlKAwQgbzRKr+6g3SVdwMByxMKiY54mYidF5Fkn:fwkGOCKbQIKL8vChm4m

Score

10^/10

tofsee evasion persistence trojan

Malware Config

Extracted

Family

tofsee

C2

vanaheim.cn

jotunheim.name

Signatures

Tofsee
Backdoor/botnet which carries out malicious activities based on commands from a C2 server.
trojan tofsee
Creates new service(s) 1 TTPs
persistence

New Service
T1050
Modifies Windows Firewall 1 TTPs 1 IoCs
evasion

Modify Existing Service
T1031

Processes:

netsh.exe

pid process

1668 netsh.exe

pid	process
1668	netsh.exe

Sets service image path in registry 2 TTPs 1 IoCs

persistence

Registry Run Keys / Startup Folder

T1060

Modify Registry

T1112

Processes:

svchost.exe

description	ioc	process
Set value (str)	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Services\dmrxxurt\ImagePath = "C:\\Windows\\SysWOW64\\dmrxxurt\\coerfewa.exe"	svchost.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:

file.exe

description ioc process

Key value queried \REGISTRY\USER\S-1-5-21-1013461898-3711306144-4198452673-1000\Control Panel\International\Geo\Nation file.exe
Executes dropped EXE 1 IoCs

Processes:

coerfewa.exe

pid process

4156 coerfewa.exe
Drops file in System32 directory 1 IoCs

Processes:

svchost.exe

description ioc process

File created C:\Windows\SysWOW64\config\systemprofile:.repos svchost.exe
Suspicious use of SetThreadContext 1 IoCs

Processes:

coerfewa.exe

description pid process target process

PID 4156 set thread context of 4848 4156 coerfewa.exe svchost.exe
Launches sc.exe 3 IoCs
Sc.exe is a Windows utlilty to control services on the system.

Processes:

sc.exesc.exesc.exe

pid process

3988 sc.exe
4716 sc.exe
4508 sc.exe
Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s).

System Information Discovery
T1082
Program crash 2 IoCs

Processes:

WerFault.exeWerFault.exe

pid pid_target process target process

2716 3340 WerFault.exe file.exe
5068 4156 WerFault.exe coerfewa.exe

description	ioc	process
Key value queried	\REGISTRY\USER\S-1-5-21-1013461898-3711306144-4198452673-1000\Control Panel\International\Geo\Nation	file.exe

pid	process
4156	coerfewa.exe

description	ioc	process
File created	C:\Windows\SysWOW64\config\systemprofile:.repos	svchost.exe

description	pid	process	target process
PID 4156 set thread context of 4848	4156	coerfewa.exe	svchost.exe

pid	process
3988	sc.exe
4716	sc.exe
4508	sc.exe

pid	pid_target	process	target process
2716	3340	WerFault.exe	file.exe
5068	4156	WerFault.exe	coerfewa.exe

Modifies data under HKEY_USERS 2 IoCs

Processes:

svchost.exe

description	ioc	process
Key created	\REGISTRY\USER\.DEFAULT\Control Panel\Buses	svchost.exe
Set value (data)	\REGISTRY\USER\.DEFAULT\Control Panel\Buses\Config0 = 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	svchost.exe

Suspicious use of WriteProcessMemory 23 IoCs

Processes:

file.execoerfewa.exe

description	pid	process	target process
PID 3340 wrote to memory of 2576	3340	file.exe	cmd.exe
PID 3340 wrote to memory of 2576	3340	file.exe	cmd.exe
PID 3340 wrote to memory of 2576	3340	file.exe	cmd.exe
PID 3340 wrote to memory of 2152	3340	file.exe	cmd.exe
PID 3340 wrote to memory of 2152	3340	file.exe	cmd.exe
PID 3340 wrote to memory of 2152	3340	file.exe	cmd.exe
PID 3340 wrote to memory of 4716	3340	file.exe	sc.exe
PID 3340 wrote to memory of 4716	3340	file.exe	sc.exe
PID 3340 wrote to memory of 4716	3340	file.exe	sc.exe
PID 3340 wrote to memory of 4508	3340	file.exe	sc.exe
PID 3340 wrote to memory of 4508	3340	file.exe	sc.exe
PID 3340 wrote to memory of 4508	3340	file.exe	sc.exe
PID 3340 wrote to memory of 3988	3340	file.exe	sc.exe
PID 3340 wrote to memory of 3988	3340	file.exe	sc.exe
PID 3340 wrote to memory of 3988	3340	file.exe	sc.exe
PID 3340 wrote to memory of 1668	3340	file.exe	netsh.exe
PID 3340 wrote to memory of 1668	3340	file.exe	netsh.exe
PID 3340 wrote to memory of 1668	3340	file.exe	netsh.exe
PID 4156 wrote to memory of 4848	4156	coerfewa.exe	svchost.exe
PID 4156 wrote to memory of 4848	4156	coerfewa.exe	svchost.exe
PID 4156 wrote to memory of 4848	4156	coerfewa.exe	svchost.exe
PID 4156 wrote to memory of 4848	4156	coerfewa.exe	svchost.exe
PID 4156 wrote to memory of 4848	4156	coerfewa.exe	svchost.exe

C:\Users\Admin\AppData\Local\Temp\file.exe
"C:\Users\Admin\AppData\Local\Temp\file.exe"
1⤵
- Checks computer location settings
- Suspicious use of WriteProcessMemory
PID:3340

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\dmrxxurt\
2⤵
PID:2576

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\coerfewa.exe" C:\Windows\SysWOW64\dmrxxurt\
2⤵
PID:2152

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" create dmrxxurt binPath= "C:\Windows\SysWOW64\dmrxxurt\coerfewa.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
2⤵
- Launches sc.exe
PID:4716

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" description dmrxxurt "wifi internet conection"
2⤵
- Launches sc.exe
PID:4508

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" start dmrxxurt
2⤵
- Launches sc.exe
PID:3988

C:\Windows\SysWOW64\netsh.exe
"C:\Windows\System32\netsh.exe" advfirewall firewall add rule name="Host-process for services of Windows" dir=in action=allow program="C:\Windows\SysWOW64\svchost.exe" enable=yes>nul
2⤵
- Modifies Windows Firewall
PID:1668

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -u -p 3340 -s 1172
2⤵
- Program crash
PID:2716

C:\Windows\SysWOW64\dmrxxurt\coerfewa.exe
C:\Windows\SysWOW64\dmrxxurt\coerfewa.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
1⤵
- Executes dropped EXE
- Suspicious use of SetThreadContext
- Suspicious use of WriteProcessMemory
PID:4156

C:\Windows\SysWOW64\svchost.exe
svchost.exe
2⤵
- Sets service image path in registry
- Drops file in System32 directory
- Modifies data under HKEY_USERS
PID:4848

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -u -p 4156 -s 508
2⤵
- Program crash
PID:5068

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 480 -p 3340 -ip 3340
1⤵
PID:3144

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 532 -p 4156 -ip 4156
1⤵
PID:4116

Network

MITRE ATT&CK Matrix ATT&CK v6

Initial Access

Execution

Persistence

New Service

1

T1050

Modify Existing Service

1

T1031

Registry Run Keys / Startup Folder

1

T1060

Privilege Escalation

New Service

1

T1050

Defense Evasion

Modify Registry

1

T1112

Credential Access

Discovery

Query Registry

1

T1012

System Information Discovery

2

T1082

Lateral Movement

Collection

Exfiltration

Command and Control

Impact

Replay Monitor

Loading Replay Monitor...

Downloads

C:\Users\Admin\AppData\Local\Temp\coerfewa.exe
Filesize
13.8MB

MD5
589a96469db9f9c051a82a10a586c7ea

SHA1
c805f17d498dc6a9ee315e44b9760cf936054664

SHA256
65d6ed315a62a55864e8865753448c6ba90e0e6d57a0c635561169ed8044e87b

SHA512
4b8725b29f2c98ad7e10bc91f0143fb945bd718cc4d4fce6da961994c59b4637991b48c1e66ba881dfd88ce90d9c1377d5f0ed1bf4c894aca8b8b0e8db9d1187

Download Submit
C:\Windows\SysWOW64\dmrxxurt\coerfewa.exe
Filesize
13.8MB

MD5
589a96469db9f9c051a82a10a586c7ea

SHA1
c805f17d498dc6a9ee315e44b9760cf936054664

SHA256
65d6ed315a62a55864e8865753448c6ba90e0e6d57a0c635561169ed8044e87b

SHA512
4b8725b29f2c98ad7e10bc91f0143fb945bd718cc4d4fce6da961994c59b4637991b48c1e66ba881dfd88ce90d9c1377d5f0ed1bf4c894aca8b8b0e8db9d1187

Download Submit
memory/3340-135-0x0000000000810000-0x0000000000823000-memory.dmp

Filesize
76KB

Download
memory/3340-138-0x0000000000400000-0x00000000006B8000-memory.dmp

Filesize
2.7MB

Download
memory/4156-144-0x0000000000400000-0x00000000006B8000-memory.dmp

Filesize
2.7MB

Download
memory/4848-140-0x0000000000C90000-0x0000000000CA5000-memory.dmp

Filesize
84KB

Download
memory/4848-143-0x0000000000C90000-0x0000000000CA5000-memory.dmp

Filesize
84KB

Download
memory/4848-145-0x0000000000C90000-0x0000000000CA5000-memory.dmp

Filesize
84KB

Download
memory/4848-146-0x0000000000C90000-0x0000000000CA5000-memory.dmp

Filesize
84KB

Download
memory/4848-148-0x0000000000C90000-0x0000000000CA5000-memory.dmp

Filesize
84KB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Matrix ATT&CK v6

Replay Monitor

Loading Replay Monitor...

Downloads