Malware Analysis Report

2025-08-05 12:50

Sample ID 240509-b4wk2sea73
Target 91e903b9fad76266ecdba9dffb7041127c7eb8983b56eae664bcebdbdcdaf852
SHA256 91e903b9fad76266ecdba9dffb7041127c7eb8983b56eae664bcebdbdcdaf852
Tags
bootkit persistence
score
6/10

Table of Contents

Analysis Overview

MITRE ATT&CK

Enterprise Matrix V15

Analysis: static1

Detonation Overview

Signatures

Analysis: behavioral1

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis: behavioral2

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis Overview

score
6/10

SHA256

91e903b9fad76266ecdba9dffb7041127c7eb8983b56eae664bcebdbdcdaf852

Threat Level: Shows suspicious behavior

The file 91e903b9fad76266ecdba9dffb7041127c7eb8983b56eae664bcebdbdcdaf852 was found to be: Shows suspicious behavior.

Malicious Activity Summary

bootkit persistence

Writes to the Master Boot Record (MBR)

Program crash

Unsigned PE

MITRE ATT&CK

Analysis: static1

Detonation Overview

Reported

2024-05-09 01:42

Signatures

Unsigned PE

Description Indicator Process Target
N/A N/A N/A N/A

Analysis: behavioral1

Detonation Overview

Submitted

2024-05-09 01:42

Reported

2024-05-09 01:45

Platform

win10v2004-20240426-en

Max time kernel

145s

Max time network

99s

Command Line

"C:\Users\Admin\AppData\Local\Temp\91e903b9fad76266ecdba9dffb7041127c7eb8983b56eae664bcebdbdcdaf852.exe"

Signatures

Writes to the Master Boot Record (MBR)

bootkit persistence
Description Indicator Process Target
File opened for modification \??\PHYSICALDRIVE0 C:\Users\Admin\AppData\Local\Temp\91e903b9fad76266ecdba9dffb7041127c7eb8983b56eae664bcebdbdcdaf852.exe N/A

Processes

C:\Users\Admin\AppData\Local\Temp\91e903b9fad76266ecdba9dffb7041127c7eb8983b56eae664bcebdbdcdaf852.exe

"C:\Users\Admin\AppData\Local\Temp\91e903b9fad76266ecdba9dffb7041127c7eb8983b56eae664bcebdbdcdaf852.exe"

C:\Windows\SysWOW64\WerFault.exe

C:\Windows\SysWOW64\WerFault.exe -pss -s 408 -p 4252 -ip 4252

C:\Windows\SysWOW64\WerFault.exe

C:\Windows\SysWOW64\WerFault.exe -u -p 4252 -s 708

Network

Country Destination Domain Proto
US 8.8.8.8:53 8.8.8.8.in-addr.arpa udp
US 8.8.8.8:53 tse1.mm.bing.net udp
US 204.79.197.200:443 tse1.mm.bing.net tcp
US 8.8.8.8:53 g.bing.com udp
US 204.79.197.237:443 g.bing.com tcp
US 8.8.8.8:53 228.249.119.40.in-addr.arpa udp
US 8.8.8.8:53 200.197.79.204.in-addr.arpa udp
US 8.8.8.8:53 0.204.248.87.in-addr.arpa udp
BE 2.17.107.105:443 www.bing.com tcp
US 8.8.8.8:53 237.197.79.204.in-addr.arpa udp
US 8.8.8.8:53 138.32.126.40.in-addr.arpa udp
US 8.8.8.8:53 105.107.17.2.in-addr.arpa udp
BE 2.17.107.105:443 www.bing.com tcp
US 8.8.8.8:53 26.35.223.20.in-addr.arpa udp
US 8.8.8.8:53 154.239.44.20.in-addr.arpa udp
US 8.8.8.8:53 50.23.12.20.in-addr.arpa udp
US 8.8.8.8:53 15.164.165.52.in-addr.arpa udp
US 8.8.8.8:53 77.190.18.2.in-addr.arpa udp
US 8.8.8.8:53 29.243.111.52.in-addr.arpa udp
US 8.8.8.8:53 tse1.mm.bing.net udp
US 204.79.197.200:443 tse1.mm.bing.net tcp
US 204.79.197.200:443 tse1.mm.bing.net tcp
US 204.79.197.200:443 tse1.mm.bing.net tcp
US 204.79.197.200:443 tse1.mm.bing.net tcp
US 8.8.8.8:53 205.47.74.20.in-addr.arpa udp

Files

memory/4252-0-0x00000000007A0000-0x00000000007A1000-memory.dmp

memory/4252-2-0x0000000000400000-0x000000000046F000-memory.dmp

memory/4252-1-0x0000000002270000-0x00000000022F0000-memory.dmp

memory/4252-3-0x0000000000400000-0x00000000004EE000-memory.dmp

memory/4252-4-0x0000000000400000-0x00000000004EE000-memory.dmp

memory/4252-7-0x0000000000400000-0x000000000046F000-memory.dmp

Analysis: behavioral2

Detonation Overview

Submitted

2024-05-09 01:42

Reported

2024-05-09 01:45

Platform

win11-20240508-en

Max time kernel

146s

Max time network

154s

Command Line

"C:\Users\Admin\AppData\Local\Temp\91e903b9fad76266ecdba9dffb7041127c7eb8983b56eae664bcebdbdcdaf852.exe"

Signatures

Writes to the Master Boot Record (MBR)

bootkit persistence
Description Indicator Process Target
File opened for modification \??\PHYSICALDRIVE0 C:\Users\Admin\AppData\Local\Temp\91e903b9fad76266ecdba9dffb7041127c7eb8983b56eae664bcebdbdcdaf852.exe N/A

Processes

C:\Users\Admin\AppData\Local\Temp\91e903b9fad76266ecdba9dffb7041127c7eb8983b56eae664bcebdbdcdaf852.exe

"C:\Users\Admin\AppData\Local\Temp\91e903b9fad76266ecdba9dffb7041127c7eb8983b56eae664bcebdbdcdaf852.exe"

C:\Windows\SysWOW64\WerFault.exe

C:\Windows\SysWOW64\WerFault.exe -pss -s 408 -p 2364 -ip 2364

C:\Windows\SysWOW64\WerFault.exe

C:\Windows\SysWOW64\WerFault.exe -u -p 2364 -s 724

Network

Country Destination Domain Proto
US 8.8.8.8:53 13.227.111.52.in-addr.arpa udp

Files

memory/2364-0-0x0000000002220000-0x0000000002221000-memory.dmp

memory/2364-1-0x00000000028B0000-0x0000000002930000-memory.dmp

memory/2364-3-0x0000000000400000-0x00000000004EE000-memory.dmp

memory/2364-2-0x0000000000400000-0x000000000046F000-memory.dmp

memory/2364-4-0x0000000000400000-0x00000000004EE000-memory.dmp

memory/2364-7-0x0000000000400000-0x000000000046F000-memory.dmp