tofsee | 924137ae8f0dfa20b25904747081d640b44c9d313548af166970c55a282ad79f

General

Target

file.exe
Size

320KB
MD5

0ff2cc1a89627650fbd3edeed0a53d02
SHA1

da5c4a1813c20dbf75a9dffe6cdd6d82e94491ab
SHA256

924137ae8f0dfa20b25904747081d640b44c9d313548af166970c55a282ad79f
SHA512

b01cb4b9358947eb14fc16b262f3b63dd252d3b2428243e0212fd0c967642410a31766820b76e81112a407b9e81ba832bf9ec7b0cda21686a578a1613a30dc67
SSDEEP

3072:yBr6yLLi1xR60YhH1qBkD9IPtbejvLhN+jXCHEuQjiMTE5xpRSag7c:ezLu160YzqSSP5IN+jXCkuQj9jaMc

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

Windows security bypass 2 TTPs 1 IoCs

evasion trojan

Disabling Security Tools

T1089

Modify Registry

T1112

Processes:

svchost.exe

description	ioc	process
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows Defender\Exclusions\Paths\C:\Windows\SysWOW64\yrznnjkm = "0"	svchost.exe

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

1512 netsh.exe

pid	process
1512	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\yrznnjkm\ImagePath = "C:\\Windows\\SysWOW64\\yrznnjkm\\dauvsaqx.exe"	svchost.exe

Deletes itself 1 IoCs

Processes:

svchost.exe

pid process

1584 svchost.exe
Executes dropped EXE 1 IoCs

Processes:

dauvsaqx.exe

pid process

1536 dauvsaqx.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:

dauvsaqx.exe

description pid process target process

PID 1536 set thread context of 1584 1536 dauvsaqx.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

1268 sc.exe
1812 sc.exe
1296 sc.exe
Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s). Likely ransomware behaviour.

System Information Discovery
T1082

pid	process
1584	svchost.exe

pid	process
1536	dauvsaqx.exe

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

description	pid	process	target process
PID 1536 set thread context of 1584	1536	dauvsaqx.exe	svchost.exe

pid	process
1268	sc.exe
1812	sc.exe
1296	sc.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 30 IoCs

Processes:

file.exedauvsaqx.exe

description	pid	process	target process
PID 1144 wrote to memory of 1360	1144	file.exe	cmd.exe
PID 1144 wrote to memory of 1360	1144	file.exe	cmd.exe
PID 1144 wrote to memory of 1360	1144	file.exe	cmd.exe
PID 1144 wrote to memory of 1360	1144	file.exe	cmd.exe
PID 1144 wrote to memory of 1232	1144	file.exe	cmd.exe
PID 1144 wrote to memory of 1232	1144	file.exe	cmd.exe
PID 1144 wrote to memory of 1232	1144	file.exe	cmd.exe
PID 1144 wrote to memory of 1232	1144	file.exe	cmd.exe
PID 1144 wrote to memory of 1296	1144	file.exe	sc.exe
PID 1144 wrote to memory of 1296	1144	file.exe	sc.exe
PID 1144 wrote to memory of 1296	1144	file.exe	sc.exe
PID 1144 wrote to memory of 1296	1144	file.exe	sc.exe
PID 1144 wrote to memory of 1268	1144	file.exe	sc.exe
PID 1144 wrote to memory of 1268	1144	file.exe	sc.exe
PID 1144 wrote to memory of 1268	1144	file.exe	sc.exe
PID 1144 wrote to memory of 1268	1144	file.exe	sc.exe
PID 1144 wrote to memory of 1812	1144	file.exe	sc.exe
PID 1144 wrote to memory of 1812	1144	file.exe	sc.exe
PID 1144 wrote to memory of 1812	1144	file.exe	sc.exe
PID 1144 wrote to memory of 1812	1144	file.exe	sc.exe
PID 1144 wrote to memory of 1512	1144	file.exe	netsh.exe
PID 1144 wrote to memory of 1512	1144	file.exe	netsh.exe
PID 1144 wrote to memory of 1512	1144	file.exe	netsh.exe
PID 1144 wrote to memory of 1512	1144	file.exe	netsh.exe
PID 1536 wrote to memory of 1584	1536	dauvsaqx.exe	svchost.exe
PID 1536 wrote to memory of 1584	1536	dauvsaqx.exe	svchost.exe
PID 1536 wrote to memory of 1584	1536	dauvsaqx.exe	svchost.exe
PID 1536 wrote to memory of 1584	1536	dauvsaqx.exe	svchost.exe
PID 1536 wrote to memory of 1584	1536	dauvsaqx.exe	svchost.exe
PID 1536 wrote to memory of 1584	1536	dauvsaqx.exe	svchost.exe

C:\Users\Admin\AppData\Local\Temp\file.exe
"C:\Users\Admin\AppData\Local\Temp\file.exe"
1⤵
- Suspicious use of WriteProcessMemory
PID:1144

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\yrznnjkm\
2⤵
PID:1360

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\dauvsaqx.exe" C:\Windows\SysWOW64\yrznnjkm\
2⤵
PID:1232

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" create yrznnjkm binPath= "C:\Windows\SysWOW64\yrznnjkm\dauvsaqx.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
2⤵
- Launches sc.exe
PID:1296

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" description yrznnjkm "wifi internet conection"
2⤵
- Launches sc.exe
PID:1268

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" start yrznnjkm
2⤵
- Launches sc.exe
PID:1812

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:1512

C:\Windows\SysWOW64\yrznnjkm\dauvsaqx.exe
C:\Windows\SysWOW64\yrznnjkm\dauvsaqx.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
1⤵
- Executes dropped EXE
- Suspicious use of SetThreadContext
- Suspicious use of WriteProcessMemory
PID:1536

C:\Windows\SysWOW64\svchost.exe
svchost.exe
2⤵
- Windows security bypass
- Sets service image path in registry
- Deletes itself
- Drops file in System32 directory
- Modifies data under HKEY_USERS
PID:1584

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

Disabling Security Tools

1

T1089

Modify Registry

2

T1112

Credential Access

Discovery

System Information Discovery

1

T1082

Lateral Movement

Collection

Exfiltration

Command and Control

Impact

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Downloads

C:\Users\Admin\AppData\Local\Temp\dauvsaqx.exe
Filesize
13.5MB

MD5
7129cead398b5a38637ffd01edf6471c

SHA1
5b961d8ea42b4f1ac3f8fa1a79fd2e4407941ce7

SHA256
af7e06dfe024ef53d124f98aefd5fd4f79ed83f663dc5b0ba0aebb4c066a95ff

SHA512
fb081a1bd27b6a2926a61134695a92dddb5c3b70b02c0918b90988b4fd00bbdb6e54fbbe50567bb08eb71b9a04fe6113c52b3fae04cdb99eef0f370b9fd82911

Download Submit
C:\Windows\SysWOW64\yrznnjkm\dauvsaqx.exe
Filesize
13.5MB

MD5
7129cead398b5a38637ffd01edf6471c

SHA1
5b961d8ea42b4f1ac3f8fa1a79fd2e4407941ce7

SHA256
af7e06dfe024ef53d124f98aefd5fd4f79ed83f663dc5b0ba0aebb4c066a95ff

SHA512
fb081a1bd27b6a2926a61134695a92dddb5c3b70b02c0918b90988b4fd00bbdb6e54fbbe50567bb08eb71b9a04fe6113c52b3fae04cdb99eef0f370b9fd82911

Download Submit
memory/1144-66-0x000000000056C000-0x0000000000581000-memory.dmp

Filesize
84KB

Download
memory/1144-56-0x000000000056C000-0x0000000000581000-memory.dmp

Filesize
84KB

Download
memory/1144-57-0x0000000000220000-0x0000000000233000-memory.dmp

Filesize
76KB

Download
memory/1144-58-0x0000000000400000-0x000000000046B000-memory.dmp

Filesize
428KB

Download
memory/1144-54-0x0000000076041000-0x0000000076043000-memory.dmp

Filesize
8KB

Download
memory/1144-67-0x0000000000400000-0x000000000046B000-memory.dmp

Filesize
428KB

Download
memory/1232-59-0x0000000000000000-mapping.dmp

Download
memory/1268-62-0x0000000000000000-mapping.dmp

Download
memory/1296-61-0x0000000000000000-mapping.dmp

Download
memory/1360-55-0x0000000000000000-mapping.dmp

Download
memory/1512-65-0x0000000000000000-mapping.dmp

Download
memory/1536-75-0x00000000002AC000-0x00000000002C1000-memory.dmp

Filesize
84KB

Download
memory/1536-77-0x0000000000400000-0x000000000046B000-memory.dmp

Filesize
428KB

Download
memory/1584-70-0x0000000000080000-0x0000000000095000-memory.dmp

Filesize
84KB

Download
memory/1584-72-0x0000000000080000-0x0000000000095000-memory.dmp

Filesize
84KB

Download
memory/1584-73-0x0000000000089A6B-mapping.dmp

Download
memory/1584-79-0x0000000000080000-0x0000000000095000-memory.dmp

Filesize
84KB

Download
memory/1584-80-0x0000000000080000-0x0000000000095000-memory.dmp

Filesize
84KB

Download
memory/1812-63-0x0000000000000000-mapping.dmp

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Matrix ATT&CK v6

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Downloads