vidar | 4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c

System Information Discovery

Processes:

4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe

description	ioc	process
Key value queried	\REGISTRY\USER\S-1-5-21-1081944012-3634099177-1681222835-1000\Control Panel\International\Geo\Nation	4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.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

9 ip-api.com

flow	ioc
9	ip-api.com

Drops file in Program Files directory 4 IoCs

Processes:

4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe

description	ioc	process
File opened for modification	C:\Program Files (x86)\LetsSee!\YTLoader.exe	4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe
File opened for modification	C:\Program Files (x86)\LetsSee!\busshost.exe	4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe
File opened for modification	C:\Program Files (x86)\LetsSee!\Uninstall.exe	4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe
File created	C:\Program Files (x86)\LetsSee!\Uninstall.ini	4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.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

4228 3544 WerFault.exe YTLoader.exe

pid	pid_target	process	target process
4228	3544	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 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
Key opened	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0	busshost.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

3996 busshost.exe
3996 busshost.exe
3996 busshost.exe
3996 busshost.exe
3996 busshost.exe
3996 busshost.exe
3996 busshost.exe
3996 busshost.exe
Suspicious use of AdjustPrivilegeToken 1 IoCs

Processes:

YTLoader.exe

description pid process

Token: SeDebugPrivilege 3544 YTLoader.exe

pid	process
3996	busshost.exe
3996	busshost.exe
3996	busshost.exe
3996	busshost.exe
3996	busshost.exe
3996	busshost.exe
3996	busshost.exe
3996	busshost.exe

description	pid	process
Token: SeDebugPrivilege	3544	YTLoader.exe

Suspicious use of WriteProcessMemory 6 IoCs

Processes:

4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe

description	pid	process	target process
PID 1152 wrote to memory of 3996	1152	4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe	busshost.exe
PID 1152 wrote to memory of 3996	1152	4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe	busshost.exe
PID 1152 wrote to memory of 3996	1152	4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe	busshost.exe
PID 1152 wrote to memory of 3544	1152	4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe	YTLoader.exe
PID 1152 wrote to memory of 3544	1152	4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe	YTLoader.exe
PID 1152 wrote to memory of 3544	1152	4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe	YTLoader.exe

C:\Users\Admin\AppData\Local\Temp\4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe
"C:\Users\Admin\AppData\Local\Temp\4a150521e422059401d4e91f084266152e0df4826e66bb1adb7a62e5768b639c.exe"
1⤵
- Checks computer location settings
- Drops file in Program Files directory
- Suspicious use of WriteProcessMemory
PID:1152

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:3996

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:3544

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -u -p 3544 -s 1624
3⤵
- Program crash
PID:4228

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 408 -p 3544 -ip 3544
1⤵
PID:212

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