tofsee | 6d1c55b32923f8a5c29fbfd3a1596bc9ef0a6f5376d8b923dcb334fc7ce97c07

General

Target

file.exe
Size

349KB
MD5

a1799db268c1e09addebda326640d27a
SHA1

2e7dd4871e0220a69c1913c974ddc5f43ee4fb25
SHA256

6d1c55b32923f8a5c29fbfd3a1596bc9ef0a6f5376d8b923dcb334fc7ce97c07
SHA512

6ead660126768007d2bb296656654867cd4a6642fccf9122415de573fc9a1644900c9b0b2342c6218ae24dae690e04868ab03ee197d5ba3aa18136eb0ae775f4
SSDEEP

3072:ix4P18aXVLB9+mTtq5qWGcjKQ10S+LwgME9WKFL6OhtWItQTIhIh3eGjMgG1ao5w:lOEVLr+mTnWr2W0S+zWY9uRjMgU

Score

10^/10

tofsee evasion persistence trojan

Malware Config

Extracted

Family

tofsee

C2

svartalfheim.top

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
Executes dropped EXE 1 IoCs

Processes:

mjdebjzg.exe

pid process

1636 mjdebjzg.exe
Modifies Windows Firewall 1 TTPs 1 IoCs
evasion

Modify Existing Service
T1031

Processes:

netsh.exe

pid process

3500 netsh.exe

pid	process
1636	mjdebjzg.exe

pid	process
3500	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\klhuoesz\ImagePath = "C:\\Windows\\SysWOW64\\klhuoesz\\mjdebjzg.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-1-5-21-2629973501-4017243118-3254762364-1000\Control Panel\International\Geo\Nation file.exe
Suspicious use of SetThreadContext 1 IoCs

Processes:

mjdebjzg.exe

description pid process target process

PID 1636 set thread context of 2644 1636 mjdebjzg.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

4720 sc.exe
1112 sc.exe
4184 sc.exe
Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s). Likely ransomware behaviour.

System Information Discovery
T1082
Program crash 2 IoCs

Processes:

WerFault.exeWerFault.exe

pid pid_target process target process

1640 5112 WerFault.exe file.exe
4704 1636 WerFault.exe mjdebjzg.exe

description	ioc	process
Key value queried	\REGISTRY\USER\S-1-5-21-2629973501-4017243118-3254762364-1000\Control Panel\International\Geo\Nation	file.exe

description	pid	process	target process
PID 1636 set thread context of 2644	1636	mjdebjzg.exe	svchost.exe

pid	process
4720	sc.exe
1112	sc.exe
4184	sc.exe

pid	pid_target	process	target process
1640	5112	WerFault.exe	file.exe
4704	1636	WerFault.exe	mjdebjzg.exe

Suspicious use of WriteProcessMemory 23 IoCs

Processes:

file.exemjdebjzg.exe

description	pid	process	target process
PID 5112 wrote to memory of 4832	5112	file.exe	cmd.exe
PID 5112 wrote to memory of 4832	5112	file.exe	cmd.exe
PID 5112 wrote to memory of 4832	5112	file.exe	cmd.exe
PID 5112 wrote to memory of 4820	5112	file.exe	cmd.exe
PID 5112 wrote to memory of 4820	5112	file.exe	cmd.exe
PID 5112 wrote to memory of 4820	5112	file.exe	cmd.exe
PID 5112 wrote to memory of 4720	5112	file.exe	sc.exe
PID 5112 wrote to memory of 4720	5112	file.exe	sc.exe
PID 5112 wrote to memory of 4720	5112	file.exe	sc.exe
PID 5112 wrote to memory of 1112	5112	file.exe	sc.exe
PID 5112 wrote to memory of 1112	5112	file.exe	sc.exe
PID 5112 wrote to memory of 1112	5112	file.exe	sc.exe
PID 5112 wrote to memory of 4184	5112	file.exe	sc.exe
PID 5112 wrote to memory of 4184	5112	file.exe	sc.exe
PID 5112 wrote to memory of 4184	5112	file.exe	sc.exe
PID 5112 wrote to memory of 3500	5112	file.exe	netsh.exe
PID 5112 wrote to memory of 3500	5112	file.exe	netsh.exe
PID 5112 wrote to memory of 3500	5112	file.exe	netsh.exe
PID 1636 wrote to memory of 2644	1636	mjdebjzg.exe	svchost.exe
PID 1636 wrote to memory of 2644	1636	mjdebjzg.exe	svchost.exe
PID 1636 wrote to memory of 2644	1636	mjdebjzg.exe	svchost.exe
PID 1636 wrote to memory of 2644	1636	mjdebjzg.exe	svchost.exe
PID 1636 wrote to memory of 2644	1636	mjdebjzg.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:5112

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\klhuoesz\
2⤵
PID:4832

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\mjdebjzg.exe" C:\Windows\SysWOW64\klhuoesz\
2⤵
PID:4820

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" create klhuoesz binPath= "C:\Windows\SysWOW64\klhuoesz\mjdebjzg.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
2⤵
- Launches sc.exe
PID:4720

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" description klhuoesz "wifi internet conection"
2⤵
- Launches sc.exe
PID:1112

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" start klhuoesz
2⤵
- Launches sc.exe
PID:4184

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:3500

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -u -p 5112 -s 1028
2⤵
- Program crash
PID:1640

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 204 -p 5112 -ip 5112
1⤵
PID:1768

C:\Windows\SysWOW64\klhuoesz\mjdebjzg.exe
C:\Windows\SysWOW64\klhuoesz\mjdebjzg.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
1⤵
- Executes dropped EXE
- Suspicious use of SetThreadContext
- Suspicious use of WriteProcessMemory
PID:1636

C:\Windows\SysWOW64\svchost.exe
svchost.exe
2⤵
- Sets service image path in registry
PID:2644

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -u -p 1636 -s 528
2⤵
- Program crash
PID:4704

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 488 -p 1636 -ip 1636
1⤵
PID:2308

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

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Downloads

C:\Users\Admin\AppData\Local\Temp\mjdebjzg.exe
Filesize
14.6MB

MD5
14ff72f4a9ed7d19cd14a60638a79e08

SHA1
a74bffbf69d43b7b5ea2850a33b96d8addfd4ba7

SHA256
91fbde6fb7dabdd5e1a2afef79ef48b4b3834eafc47a5a6890fec242c93e8da2

SHA512
0bf0598450637e2aba5cbcfff2853c99db3f4ab5c958c511f6ee7058e67a0e7ba46bbbdff006d791300c6b167da6f6516be59817a67a3750c7abdd54939eaa92

Download Submit
C:\Windows\SysWOW64\klhuoesz\mjdebjzg.exe
Filesize
14.6MB

MD5
14ff72f4a9ed7d19cd14a60638a79e08

SHA1
a74bffbf69d43b7b5ea2850a33b96d8addfd4ba7

SHA256
91fbde6fb7dabdd5e1a2afef79ef48b4b3834eafc47a5a6890fec242c93e8da2

SHA512
0bf0598450637e2aba5cbcfff2853c99db3f4ab5c958c511f6ee7058e67a0e7ba46bbbdff006d791300c6b167da6f6516be59817a67a3750c7abdd54939eaa92

Download Submit
memory/1112-139-0x0000000000000000-mapping.dmp

Download
memory/1636-149-0x0000000000400000-0x000000000045C000-memory.dmp

Filesize
368KB

Download
memory/1636-148-0x0000000000542000-0x0000000000557000-memory.dmp

Filesize
84KB

Download
memory/2644-151-0x0000000000C20000-0x0000000000C35000-memory.dmp

Filesize
84KB

Download
memory/2644-150-0x0000000000C20000-0x0000000000C35000-memory.dmp

Filesize
84KB

Download
memory/2644-145-0x0000000000C20000-0x0000000000C35000-memory.dmp

Filesize
84KB

Download
memory/2644-144-0x0000000000000000-mapping.dmp

Download
memory/3500-141-0x0000000000000000-mapping.dmp

Download
memory/4184-140-0x0000000000000000-mapping.dmp

Download
memory/4720-138-0x0000000000000000-mapping.dmp

Download
memory/4820-136-0x0000000000000000-mapping.dmp

Download
memory/4832-135-0x0000000000000000-mapping.dmp

Download
memory/5112-143-0x0000000000400000-0x000000000045C000-memory.dmp

Filesize
368KB

Download
memory/5112-132-0x0000000000697000-0x00000000006AC000-memory.dmp

Filesize
84KB

Download
memory/5112-134-0x0000000000400000-0x000000000045C000-memory.dmp

Filesize
368KB

Download
memory/5112-133-0x00000000004A0000-0x00000000004B3000-memory.dmp

Filesize
76KB

Download

Analysis

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