tofsee | ef514682a7ab092326100883aa5a4101cb49a2054f538e3731d80c19e065f016

General

Target

file.exe
Size

350KB
MD5

64b84c266e164427f5ff999f0852817c
SHA1

2ac627bc23ec6669c2d8a95f6c3f35c6e1e753a9
SHA256

ef514682a7ab092326100883aa5a4101cb49a2054f538e3731d80c19e065f016
SHA512

f1e36be5e459c71eef8c3880d3cb905bf7f4f909fe00bafb255b45e89b1657cbb3cb6596ffe91751fe690dd7d1923ad8884a4198813ce4a0253ea4025c9ff69b
SSDEEP

6144:Y825LbuPCD71fzEEtPBYNd2LNDRyjkuRjMgU:Y7nuKRlRKd2RDA1RQg

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:

jzfmrdhw.exe

pid process

2188 jzfmrdhw.exe
Modifies Windows Firewall 1 TTPs 1 IoCs
evasion

Modify Existing Service
T1031

Processes:

netsh.exe

pid process

176 netsh.exe

pid	process
2188	jzfmrdhw.exe

pid	process
176	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\zsvpnckr\ImagePath = "C:\\Windows\\SysWOW64\\zsvpnckr\\jzfmrdhw.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-1-5-21-2891029575-1462575-1165213807-1000\Control Panel\International\Geo\Nation file.exe
Suspicious use of SetThreadContext 1 IoCs

Processes:

jzfmrdhw.exe

description pid process target process

PID 2188 set thread context of 2712 2188 jzfmrdhw.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

1776 sc.exe
3444 sc.exe
2012 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

3664 2992 WerFault.exe file.exe
2568 2188 WerFault.exe jzfmrdhw.exe

description	ioc	process
Key value queried	\REGISTRY\USER\S-1-5-21-2891029575-1462575-1165213807-1000\Control Panel\International\Geo\Nation	file.exe

description	pid	process	target process
PID 2188 set thread context of 2712	2188	jzfmrdhw.exe	svchost.exe

pid	process
1776	sc.exe
3444	sc.exe
2012	sc.exe

pid	pid_target	process	target process
3664	2992	WerFault.exe	file.exe
2568	2188	WerFault.exe	jzfmrdhw.exe

Suspicious use of WriteProcessMemory 23 IoCs

Processes:

file.exejzfmrdhw.exe

description	pid	process	target process
PID 2992 wrote to memory of 4944	2992	file.exe	cmd.exe
PID 2992 wrote to memory of 4944	2992	file.exe	cmd.exe
PID 2992 wrote to memory of 4944	2992	file.exe	cmd.exe
PID 2992 wrote to memory of 4936	2992	file.exe	cmd.exe
PID 2992 wrote to memory of 4936	2992	file.exe	cmd.exe
PID 2992 wrote to memory of 4936	2992	file.exe	cmd.exe
PID 2992 wrote to memory of 3444	2992	file.exe	sc.exe
PID 2992 wrote to memory of 3444	2992	file.exe	sc.exe
PID 2992 wrote to memory of 3444	2992	file.exe	sc.exe
PID 2992 wrote to memory of 2012	2992	file.exe	sc.exe
PID 2992 wrote to memory of 2012	2992	file.exe	sc.exe
PID 2992 wrote to memory of 2012	2992	file.exe	sc.exe
PID 2992 wrote to memory of 1776	2992	file.exe	sc.exe
PID 2992 wrote to memory of 1776	2992	file.exe	sc.exe
PID 2992 wrote to memory of 1776	2992	file.exe	sc.exe
PID 2992 wrote to memory of 176	2992	file.exe	netsh.exe
PID 2992 wrote to memory of 176	2992	file.exe	netsh.exe
PID 2992 wrote to memory of 176	2992	file.exe	netsh.exe
PID 2188 wrote to memory of 2712	2188	jzfmrdhw.exe	svchost.exe
PID 2188 wrote to memory of 2712	2188	jzfmrdhw.exe	svchost.exe
PID 2188 wrote to memory of 2712	2188	jzfmrdhw.exe	svchost.exe
PID 2188 wrote to memory of 2712	2188	jzfmrdhw.exe	svchost.exe
PID 2188 wrote to memory of 2712	2188	jzfmrdhw.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:2992

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\zsvpnckr\
2⤵
PID:4944

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\jzfmrdhw.exe" C:\Windows\SysWOW64\zsvpnckr\
2⤵
PID:4936

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" create zsvpnckr binPath= "C:\Windows\SysWOW64\zsvpnckr\jzfmrdhw.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
2⤵
- Launches sc.exe
PID:3444

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" description zsvpnckr "wifi internet conection"
2⤵
- Launches sc.exe
PID:2012

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" start zsvpnckr
2⤵
- Launches sc.exe
PID:1776

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:176

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -u -p 2992 -s 1160
2⤵
- Program crash
PID:3664

C:\Windows\SysWOW64\zsvpnckr\jzfmrdhw.exe
C:\Windows\SysWOW64\zsvpnckr\jzfmrdhw.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
1⤵
- Executes dropped EXE
- Suspicious use of SetThreadContext
- Suspicious use of WriteProcessMemory
PID:2188

C:\Windows\SysWOW64\svchost.exe
svchost.exe
2⤵
- Sets service image path in registry
PID:2712

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -u -p 2188 -s 556
2⤵
- Program crash
PID:2568

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 456 -p 2992 -ip 2992
1⤵
PID:3764

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 404 -p 2188 -ip 2188
1⤵
PID:2272

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\jzfmrdhw.exe
Filesize
11.7MB

MD5
88fd4233bb42bd785fad42b5f0f7691c

SHA1
7013e45617bfa43be8c4b6b4f7c99bdba2d25053

SHA256
39a9b786df0ddf55a0646de35f970d4e08e44aa1a631a802cc83ac73bd5c0195

SHA512
71f923b702c7f68df63667f796819381847c4ebe627170855d47b41b4e68eb8baaf82fb3c9e2c6a240789ece23be133317556ac61583a23329aa1a8a80eb96f9

Download Submit
C:\Windows\SysWOW64\zsvpnckr\jzfmrdhw.exe
Filesize
11.7MB

MD5
88fd4233bb42bd785fad42b5f0f7691c

SHA1
7013e45617bfa43be8c4b6b4f7c99bdba2d25053

SHA256
39a9b786df0ddf55a0646de35f970d4e08e44aa1a631a802cc83ac73bd5c0195

SHA512
71f923b702c7f68df63667f796819381847c4ebe627170855d47b41b4e68eb8baaf82fb3c9e2c6a240789ece23be133317556ac61583a23329aa1a8a80eb96f9

Download Submit
memory/176-144-0x0000000000000000-mapping.dmp

Download
memory/1776-142-0x0000000000000000-mapping.dmp

Download
memory/2012-139-0x0000000000000000-mapping.dmp

Download
memory/2188-151-0x0000000000400000-0x000000000045D000-memory.dmp

Filesize
372KB

Download
memory/2188-150-0x0000000000552000-0x0000000000567000-memory.dmp

Filesize
84KB

Download
memory/2712-146-0x0000000000000000-mapping.dmp

Download
memory/2712-153-0x0000000000520000-0x0000000000535000-memory.dmp

Filesize
84KB

Download
memory/2712-152-0x0000000000520000-0x0000000000535000-memory.dmp

Filesize
84KB

Download
memory/2712-147-0x0000000000520000-0x0000000000535000-memory.dmp

Filesize
84KB

Download
memory/2992-140-0x0000000000757000-0x000000000076C000-memory.dmp

Filesize
84KB

Download
memory/2992-133-0x0000000000570000-0x0000000000583000-memory.dmp

Filesize
76KB

Download
memory/2992-145-0x0000000000400000-0x000000000045D000-memory.dmp

Filesize
372KB

Download
memory/2992-134-0x0000000000400000-0x000000000045D000-memory.dmp

Filesize
372KB

Download
memory/2992-132-0x0000000000757000-0x000000000076C000-memory.dmp

Filesize
84KB

Download
memory/2992-141-0x0000000000570000-0x0000000000583000-memory.dmp

Filesize
76KB

Download
memory/3444-138-0x0000000000000000-mapping.dmp

Download
memory/4936-136-0x0000000000000000-mapping.dmp

Download
memory/4944-135-0x0000000000000000-mapping.dmp

Download

Analysis

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