tofsee | 8009c5bc8df7fb418791fe8ec56e58ee257ef1dcddbe47a8dfe180b6fee3b390

General

Target

file.exe
Size

299KB
MD5

1c5c5fcbb9411738d3e6945a538522c9
SHA1

e9f3e00bb4f5a3035481d05d7429c825bd16ab7b
SHA256

8009c5bc8df7fb418791fe8ec56e58ee257ef1dcddbe47a8dfe180b6fee3b390
SHA512

e580b9531d14e3fe0264559d70f43b7d8a8a77ab32b52d3d5e919b96871af264b4886e55752e9feefa352746846ea1310cb5ef49cd3a81643b822e8d70878947
SSDEEP

3072:3zb6bLKLLCeRmSULtjK0h13Di9+6QtXxp+q0rsL4spqIuQjiMTE5JOPa5H:j0KLLCdSuR1zis6QtXxYTN+qIuQj9ja

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\gegwfaxa = "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

1956 netsh.exe

pid	process
1956	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\gegwfaxa\ImagePath = "C:\\Windows\\SysWOW64\\gegwfaxa\\yohfclsr.exe"	svchost.exe

Deletes itself 1 IoCs

Processes:

svchost.exe

pid process

1852 svchost.exe
Executes dropped EXE 1 IoCs

Processes:

yohfclsr.exe

pid process

1260 yohfclsr.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:

yohfclsr.exe

description pid process target process

PID 1260 set thread context of 1852 1260 yohfclsr.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

1504 sc.exe
1656 sc.exe
1972 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
1852	svchost.exe

pid	process
1260	yohfclsr.exe

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

description	pid	process	target process
PID 1260 set thread context of 1852	1260	yohfclsr.exe	svchost.exe

pid	process
1504	sc.exe
1656	sc.exe
1972	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.exeyohfclsr.exe

description	pid	process	target process
PID 2040 wrote to memory of 1336	2040	file.exe	cmd.exe
PID 2040 wrote to memory of 1336	2040	file.exe	cmd.exe
PID 2040 wrote to memory of 1336	2040	file.exe	cmd.exe
PID 2040 wrote to memory of 1336	2040	file.exe	cmd.exe
PID 2040 wrote to memory of 1640	2040	file.exe	cmd.exe
PID 2040 wrote to memory of 1640	2040	file.exe	cmd.exe
PID 2040 wrote to memory of 1640	2040	file.exe	cmd.exe
PID 2040 wrote to memory of 1640	2040	file.exe	cmd.exe
PID 2040 wrote to memory of 1504	2040	file.exe	sc.exe
PID 2040 wrote to memory of 1504	2040	file.exe	sc.exe
PID 2040 wrote to memory of 1504	2040	file.exe	sc.exe
PID 2040 wrote to memory of 1504	2040	file.exe	sc.exe
PID 2040 wrote to memory of 1656	2040	file.exe	sc.exe
PID 2040 wrote to memory of 1656	2040	file.exe	sc.exe
PID 2040 wrote to memory of 1656	2040	file.exe	sc.exe
PID 2040 wrote to memory of 1656	2040	file.exe	sc.exe
PID 2040 wrote to memory of 1972	2040	file.exe	sc.exe
PID 2040 wrote to memory of 1972	2040	file.exe	sc.exe
PID 2040 wrote to memory of 1972	2040	file.exe	sc.exe
PID 2040 wrote to memory of 1972	2040	file.exe	sc.exe
PID 2040 wrote to memory of 1956	2040	file.exe	netsh.exe
PID 2040 wrote to memory of 1956	2040	file.exe	netsh.exe
PID 2040 wrote to memory of 1956	2040	file.exe	netsh.exe
PID 2040 wrote to memory of 1956	2040	file.exe	netsh.exe
PID 1260 wrote to memory of 1852	1260	yohfclsr.exe	svchost.exe
PID 1260 wrote to memory of 1852	1260	yohfclsr.exe	svchost.exe
PID 1260 wrote to memory of 1852	1260	yohfclsr.exe	svchost.exe
PID 1260 wrote to memory of 1852	1260	yohfclsr.exe	svchost.exe
PID 1260 wrote to memory of 1852	1260	yohfclsr.exe	svchost.exe
PID 1260 wrote to memory of 1852	1260	yohfclsr.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:2040

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /C mkdir C:\Windows\SysWOW64\gegwfaxa\
2⤵
PID:1336

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /C move /Y "C:\Users\Admin\AppData\Local\Temp\yohfclsr.exe" C:\Windows\SysWOW64\gegwfaxa\
2⤵
PID:1640

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" create gegwfaxa binPath= "C:\Windows\SysWOW64\gegwfaxa\yohfclsr.exe /d\"C:\Users\Admin\AppData\Local\Temp\file.exe\"" type= own start= auto DisplayName= "wifi support"
2⤵
- Launches sc.exe
PID:1504

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" description gegwfaxa "wifi internet conection"
2⤵
- Launches sc.exe
PID:1656

C:\Windows\SysWOW64\sc.exe
"C:\Windows\System32\sc.exe" start gegwfaxa
2⤵
- Launches sc.exe
PID:1972

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:1956

C:\Windows\SysWOW64\gegwfaxa\yohfclsr.exe
C:\Windows\SysWOW64\gegwfaxa\yohfclsr.exe /d"C:\Users\Admin\AppData\Local\Temp\file.exe"
1⤵
- Executes dropped EXE
- Suspicious use of SetThreadContext
- Suspicious use of WriteProcessMemory
PID:1260

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:1852

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Modify Existing Service

New Service

Registry Run Keys / Startup Folder

1

T1060

Privilege Escalation

New Service

1

T1050

Defense Evasion

Disabling Security Tools

Modify Registry

Credential Access

Discovery

System Information Discovery

1

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

C:\Users\Admin\AppData\Local\Temp\yohfclsr.exe
Filesize
14.1MB

MD5
6d3cb55d09981c7e17bd8b820ae9e961

SHA1
1915f216420e5449235e0ddf37efcb5f658bf5cb

SHA256
d4d77a208904bd9bdc13c886d3512a7119f2bdb49b9a4c2dfa2b80bb98aca093

SHA512
b8dcd98860529cca42d633438e1f6791f3ec5706879ec68f64a4875d8a1939edad545d8ca884cd547e114898c3caf3c6e51e4b4715d65e44d2a36b59f3f54658

Download Submit
C:\Windows\SysWOW64\gegwfaxa\yohfclsr.exe
Filesize
14.1MB

MD5
6d3cb55d09981c7e17bd8b820ae9e961

SHA1
1915f216420e5449235e0ddf37efcb5f658bf5cb

SHA256
d4d77a208904bd9bdc13c886d3512a7119f2bdb49b9a4c2dfa2b80bb98aca093

SHA512
b8dcd98860529cca42d633438e1f6791f3ec5706879ec68f64a4875d8a1939edad545d8ca884cd547e114898c3caf3c6e51e4b4715d65e44d2a36b59f3f54658

Download Submit
memory/1260-74-0x000000000057C000-0x0000000000591000-memory.dmp

Filesize
84KB

Download
memory/1260-76-0x0000000000400000-0x00000000004C7000-memory.dmp

Filesize
796KB

Download
memory/1336-58-0x0000000000000000-mapping.dmp

Download
memory/1504-61-0x0000000000000000-mapping.dmp

Download
memory/1640-59-0x0000000000000000-mapping.dmp

Download
memory/1656-62-0x0000000000000000-mapping.dmp

Download
memory/1852-79-0x0000000000080000-0x0000000000095000-memory.dmp

Filesize
84KB

Download
memory/1852-73-0x0000000000089A6B-mapping.dmp

Download
memory/1852-85-0x0000000000080000-0x0000000000095000-memory.dmp

Filesize
84KB

Download
memory/1852-83-0x00000000000C0000-0x00000000000C6000-memory.dmp

Filesize
24KB

Download
memory/1852-72-0x0000000000080000-0x0000000000095000-memory.dmp

Filesize
84KB

Download
memory/1852-80-0x0000000001900000-0x0000000001B0F000-memory.dmp

Filesize
2.1MB

Download
memory/1852-70-0x0000000000080000-0x0000000000095000-memory.dmp

Filesize
84KB

Download
memory/1956-65-0x0000000000000000-mapping.dmp

Download
memory/1972-63-0x0000000000000000-mapping.dmp

Download
memory/2040-57-0x0000000000400000-0x00000000004C7000-memory.dmp

Filesize
796KB

Download
memory/2040-56-0x0000000000220000-0x0000000000233000-memory.dmp

Filesize
76KB

Download
memory/2040-54-0x0000000076651000-0x0000000076653000-memory.dmp

Filesize
8KB

Download
memory/2040-67-0x0000000000400000-0x00000000004C7000-memory.dmp

Filesize
796KB

Download
memory/2040-66-0x000000000064C000-0x0000000000661000-memory.dmp

Filesize
84KB

Download
memory/2040-55-0x000000000064C000-0x0000000000661000-memory.dmp

Filesize
84KB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v6

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Downloads