tofsee | ae103a988f889f4120a5d21bdf08d4ff41588c26c4efab1c604cab29dc5632a2

General

Target

file.exe
Size

178KB
MD5

faca2fb4b7df8b02263be3f101775d8d
SHA1

1ee11a0311a1507b66d76b668eaa1806794692a7
SHA256

ae103a988f889f4120a5d21bdf08d4ff41588c26c4efab1c604cab29dc5632a2
SHA512

3f8dd1204b45afb76df8137f1a46a40a6b53c3bf98b80959724d27bc1da1e1e48fb28c18ebbb4940b30ac6b98e1b04f4ccb937e7a9b836802bfbea903a88ff7c
SSDEEP

3072:knSQXMYrEDcw6d5QWBhf7RBkDuaad402UlVDYJ5V2RBB2Wk2:mDEDcwdYJRBSuld40vYJ5yB

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:

zprevny.exe

pid process

2004 zprevny.exe
Modifies Windows Firewall 1 TTPs 1 IoCs
evasion

Modify Existing Service
T1031

Processes:

netsh.exe

pid process

700 netsh.exe

pid	process
2004	zprevny.exe

pid	process
700	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\nivommpg\ImagePath = "C:\\Windows\\SysWOW64\\nivommpg\\zprevny.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-1-5-21-2386679933-1492765628-3466841596-1000\Control Panel\International\Geo\Nation file.exe
Suspicious use of SetThreadContext 1 IoCs

Processes:

zprevny.exe

description pid process target process

PID 2004 set thread context of 1832 2004 zprevny.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

4124 sc.exe
880 sc.exe
3104 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

452 2004 WerFault.exe zprevny.exe
64 4504 WerFault.exe file.exe

description	ioc	process
Key value queried	\REGISTRY\USER\S-1-5-21-2386679933-1492765628-3466841596-1000\Control Panel\International\Geo\Nation	file.exe

description	pid	process	target process
PID 2004 set thread context of 1832	2004	zprevny.exe	svchost.exe

pid	process
4124	sc.exe
880	sc.exe
3104	sc.exe

pid	pid_target	process	target process
452	2004	WerFault.exe	zprevny.exe
64	4504	WerFault.exe	file.exe

Suspicious use of WriteProcessMemory 23 IoCs

Processes:

file.exezprevny.exe

description	pid	process	target process
PID 4504 wrote to memory of 3548	4504	file.exe	cmd.exe
PID 4504 wrote to memory of 3548	4504	file.exe	cmd.exe
PID 4504 wrote to memory of 3548	4504	file.exe	cmd.exe
PID 4504 wrote to memory of 396	4504	file.exe	cmd.exe
PID 4504 wrote to memory of 396	4504	file.exe	cmd.exe
PID 4504 wrote to memory of 396	4504	file.exe	cmd.exe
PID 4504 wrote to memory of 4124	4504	file.exe	sc.exe
PID 4504 wrote to memory of 4124	4504	file.exe	sc.exe
PID 4504 wrote to memory of 4124	4504	file.exe	sc.exe
PID 4504 wrote to memory of 880	4504	file.exe	sc.exe
PID 4504 wrote to memory of 880	4504	file.exe	sc.exe
PID 4504 wrote to memory of 880	4504	file.exe	sc.exe
PID 4504 wrote to memory of 3104	4504	file.exe	sc.exe
PID 4504 wrote to memory of 3104	4504	file.exe	sc.exe
PID 4504 wrote to memory of 3104	4504	file.exe	sc.exe
PID 4504 wrote to memory of 700	4504	file.exe	netsh.exe
PID 4504 wrote to memory of 700	4504	file.exe	netsh.exe
PID 4504 wrote to memory of 700	4504	file.exe	netsh.exe
PID 2004 wrote to memory of 1832	2004	zprevny.exe	svchost.exe
PID 2004 wrote to memory of 1832	2004	zprevny.exe	svchost.exe
PID 2004 wrote to memory of 1832	2004	zprevny.exe	svchost.exe
PID 2004 wrote to memory of 1832	2004	zprevny.exe	svchost.exe
PID 2004 wrote to memory of 1832	2004	zprevny.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:4504

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\nivommpg\
2⤵
PID:3548

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\zprevny.exe" C:\Windows\SysWOW64\nivommpg\
2⤵
PID:396

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" create nivommpg binPath= "C:\Windows\SysWOW64\nivommpg\zprevny.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
2⤵
- Launches sc.exe
PID:4124

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" description nivommpg "wifi internet conection"
2⤵
- Launches sc.exe
PID:880

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" start nivommpg
2⤵
- Launches sc.exe
PID:3104

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:700

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -u -p 4504 -s 1208
2⤵
- Program crash
PID:64

C:\Windows\SysWOW64\nivommpg\zprevny.exe
C:\Windows\SysWOW64\nivommpg\zprevny.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
1⤵
- Executes dropped EXE
- Suspicious use of SetThreadContext
- Suspicious use of WriteProcessMemory
PID:2004

C:\Windows\SysWOW64\svchost.exe
svchost.exe
2⤵
- Sets service image path in registry
PID:1832

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -u -p 2004 -s 508
2⤵
- Program crash
PID:452

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 208 -p 4504 -ip 4504
1⤵
PID:1896

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 484 -p 2004 -ip 2004
1⤵
PID:2496

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\zprevny.exe
Filesize
14.8MB

MD5
d71f9a5ac0fd6c7071cc3582dacf425d

SHA1
465f4cbe14cdef523d3e85b2ea96d79a85decf18

SHA256
0855ccd720086d5c49168e5b83aba39f92abb24e238983660f9f0aa5878d1b7a

SHA512
1f4cb1886ea645b34839089bb24b23f9f0782830a5b37cc5310594b0edeb0ae4b6ad8559fca3ad3d56553c1375bc02ce1fa4afabe9a083df8e846905373fe866

Download Submit
C:\Windows\SysWOW64\nivommpg\zprevny.exe
Filesize
14.8MB

MD5
d71f9a5ac0fd6c7071cc3582dacf425d

SHA1
465f4cbe14cdef523d3e85b2ea96d79a85decf18

SHA256
0855ccd720086d5c49168e5b83aba39f92abb24e238983660f9f0aa5878d1b7a

SHA512
1f4cb1886ea645b34839089bb24b23f9f0782830a5b37cc5310594b0edeb0ae4b6ad8559fca3ad3d56553c1375bc02ce1fa4afabe9a083df8e846905373fe866

Download Submit
memory/396-136-0x0000000000000000-mapping.dmp

Download
memory/700-141-0x0000000000000000-mapping.dmp

Download
memory/880-139-0x0000000000000000-mapping.dmp

Download
memory/1832-152-0x0000000000580000-0x0000000000595000-memory.dmp

Filesize
84KB

Download
memory/1832-151-0x0000000000580000-0x0000000000595000-memory.dmp

Filesize
84KB

Download
memory/1832-146-0x0000000000580000-0x0000000000595000-memory.dmp

Filesize
84KB

Download
memory/1832-145-0x0000000000000000-mapping.dmp

Download
memory/2004-147-0x00000000008D8000-0x00000000008E8000-memory.dmp

Filesize
64KB

Download
memory/2004-148-0x0000000000400000-0x000000000070E000-memory.dmp

Filesize
3.1MB

Download
memory/3104-140-0x0000000000000000-mapping.dmp

Download
memory/3548-135-0x0000000000000000-mapping.dmp

Download
memory/4124-138-0x0000000000000000-mapping.dmp

Download
memory/4504-142-0x00000000009DD000-0x00000000009EE000-memory.dmp

Filesize
68KB

Download
memory/4504-143-0x0000000000400000-0x000000000070E000-memory.dmp

Filesize
3.1MB

Download
memory/4504-133-0x0000000000850000-0x0000000000863000-memory.dmp

Filesize
76KB

Download
memory/4504-134-0x0000000000400000-0x000000000070E000-memory.dmp

Filesize
3.1MB

Download
memory/4504-132-0x00000000009DD000-0x00000000009EE000-memory.dmp

Filesize
68KB

Download

Analysis

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