vidar | 4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba

System Information Discovery

Processes:

4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe

description	ioc	process
Key value queried	\REGISTRY\USER\S-1-5-21-2632097139-1792035885-811742494-1000\Control Panel\International\Geo\Nation	4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe

Reads local data of messenger clients 2 TTPs
Infostealers often target stored data of messaging applications, which can include saved credentials and account information.
spyware stealer

Data from Local System
T1005

Credentials in Files
T1081
Reads user/profile data of local email clients 2 TTPs
Email clients store some user data on disk where infostealers will often target it.
spyware stealer

Data from Local System
T1005

Credentials in Files
T1081
Reads user/profile data of web browsers 2 TTPs
Infostealers often target stored browser data, which can include saved credentials etc.
spyware stealer

Data from Local System
T1005

Credentials in Files
T1081
Accesses 2FA software files, possible credential harvesting 2 TTPs
spyware stealer

Data from Local System
T1005

Credentials in Files
T1081
Checks installed software on the system 1 TTPs
Looks up Uninstall key entries in the registry to enumerate software on the system.
discovery

Query Registry
T1012
Looks up external IP address via web service 1 IoCs
Uses a legitimate IP lookup service to find the infected system's external IP.

Processes:

flow ioc

15 ip-api.com

flow	ioc
15	ip-api.com

Drops file in Program Files directory 4 IoCs

Processes:

4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe

description	ioc	process
File created	C:\Program Files (x86)\LetsSee!\Uninstall.ini	4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe
File opened for modification	C:\Program Files (x86)\LetsSee!\YTLoader.exe	4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe
File opened for modification	C:\Program Files (x86)\LetsSee!\busshost.exe	4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe
File opened for modification	C:\Program Files (x86)\LetsSee!\Uninstall.exe	4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.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 1 IoCs

Processes:

WerFault.exe

pid pid_target process target process

4772 4920 WerFault.exe YTLoader.exe

pid	pid_target	process	target process
4772	4920	WerFault.exe	YTLoader.exe

Checks processor information in registry 2 TTPs 4 IoCs

Processor information is often read in order to detect sandboxing environments.

Query Registry

System Information Discovery

Processes:

busshost.exeYTLoader.exe

description	ioc	process
Key opened	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0	busshost.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\ProcessorNameString	busshost.exe
Key opened	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0	YTLoader.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\ProcessorNameString	YTLoader.exe

Enumerates system info in registry 2 TTPs 3 IoCs

Query Registry

System Information Discovery

Processes:

YTLoader.exe

description	ioc	process
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\BIOS\SystemManufacturer	YTLoader.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\BIOS\SystemProductName	YTLoader.exe
Key opened	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\BIOS	YTLoader.exe

Suspicious behavior: EnumeratesProcesses 8 IoCs

Processes:

busshost.exe

pid process

2104 busshost.exe
2104 busshost.exe
2104 busshost.exe
2104 busshost.exe
2104 busshost.exe
2104 busshost.exe
2104 busshost.exe
2104 busshost.exe
Suspicious use of AdjustPrivilegeToken 1 IoCs

Processes:

YTLoader.exe

description pid process

Token: SeDebugPrivilege 4920 YTLoader.exe

pid	process
2104	busshost.exe
2104	busshost.exe
2104	busshost.exe
2104	busshost.exe
2104	busshost.exe
2104	busshost.exe
2104	busshost.exe
2104	busshost.exe

description	pid	process
Token: SeDebugPrivilege	4920	YTLoader.exe

Suspicious use of WriteProcessMemory 6 IoCs

Processes:

4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe

description	pid	process	target process
PID 4744 wrote to memory of 2104	4744	4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe	busshost.exe
PID 4744 wrote to memory of 2104	4744	4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe	busshost.exe
PID 4744 wrote to memory of 2104	4744	4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe	busshost.exe
PID 4744 wrote to memory of 4920	4744	4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe	YTLoader.exe
PID 4744 wrote to memory of 4920	4744	4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe	YTLoader.exe
PID 4744 wrote to memory of 4920	4744	4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe	YTLoader.exe

C:\Users\Admin\AppData\Local\Temp\4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe
"C:\Users\Admin\AppData\Local\Temp\4135938f1fdf73960b444fb49177b35a46fe71893456ea9572de215b40ee41ba.exe"
1⤵
- Checks computer location settings
- Drops file in Program Files directory
- Suspicious use of WriteProcessMemory
PID:4744

C:\Program Files (x86)\LetsSee!\busshost.exe
"C:\Program Files (x86)\LetsSee!\busshost.exe"
2⤵
- Executes dropped EXE
- Checks processor information in registry
- Suspicious behavior: EnumeratesProcesses
PID:2104

C:\Program Files (x86)\LetsSee!\YTLoader.exe
"C:\Program Files (x86)\LetsSee!\YTLoader.exe"
2⤵
- Executes dropped EXE
- Checks processor information in registry
- Enumerates system info in registry
- Suspicious use of AdjustPrivilegeToken
PID:4920

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -u -p 4920 -s 1616
3⤵
- Program crash
PID:4772

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 408 -p 4920 -ip 4920
1⤵
PID:3604

Network

MITRE ATT&CK Matrix ATT&CK v6

Initial Access

Execution

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Credentials in Files

T1081

Discovery

Query Registry

System Information Discovery

Lateral Movement

Collection

Data from Local System