buer | 63e6f759e7978643e5b7998f737688b8a5c08ad0ce843ba20822c7d9125e4714

General

Target

Private document.docm
Size

2.0MB
MD5

526e3392d7634da433db9ae9dce6a9b6
SHA1

f182af125f4b8b0953ab2755e50dc5a8ba3294c9
SHA256

63e6f759e7978643e5b7998f737688b8a5c08ad0ce843ba20822c7d9125e4714
SHA512

961d2b015376d723023f55659b9c1d3f7bdccf934d73c751cb7acf1fa8685a5e88308c8feb31bc132487d243c060b2fdcd2c176a1d1dd23d0c22339f342aeab1

Score

10^/10

buer loader

Malware Config

Extracted

Family

buer

C2

cembank-api.com

Signatures

Buer
Buer is a new modular loader first seen in August 2019.
loader buer

Process spawned unexpected child process 1 IoCs

This typically indicates the parent process was compromised via an exploit or macro.

description	pid	pid_target	Process	procid_target
Parent C:\Program Files\Microsoft Office\Root\Office16\WINWORD.EXE is not expected to spawn this process	1204	616	rundll32.exe	68

Buer Loader 1 IoCs

Detects Buer loader in memory or disk.

resource	yara_rule
behavioral2/memory/3524-14-0x0000000040000000-0x000000004000A000-memory.dmp	buer

Executes dropped EXE 2 IoCs

pid	Process
2296	Office_WorkForWestBank.exe
3524	Office_WorkForWestBank.exe

Loads dropped DLL 1 IoCs

pid	Process
2296	Office_WorkForWestBank.exe

Suspicious use of SetThreadContext 1 IoCs

description	pid	Process	procid_target
PID 2296 set thread context of 3524	2296	Office_WorkForWestBank.exe	84

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

System Information Discovery
T1082

NSIS installer 6 IoCs

installer

resource	yara_rule
behavioral2/files/0x000200000001ab7b-9.dat	nsis_installer_1
behavioral2/files/0x000200000001ab7b-9.dat	nsis_installer_2
behavioral2/files/0x000200000001ab7b-10.dat	nsis_installer_1
behavioral2/files/0x000200000001ab7b-10.dat	nsis_installer_2
behavioral2/files/0x000200000001ab7b-13.dat	nsis_installer_1
behavioral2/files/0x000200000001ab7b-13.dat	nsis_installer_2

Checks processor information in registry 2 TTPs 3 IoCs

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

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key opened	\REGISTRY\MACHINE\Hardware\Description\System\CentralProcessor\0	WINWORD.EXE
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\~MHz	WINWORD.EXE
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\ProcessorNameString	WINWORD.EXE

Enumerates system info in registry 2 TTPs 3 IoCs

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key opened	\REGISTRY\MACHINE\Hardware\Description\System\BIOS	WINWORD.EXE
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\BIOS\SystemFamily	WINWORD.EXE
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\BIOS\SystemSKU	WINWORD.EXE

Suspicious behavior: AddClipboardFormatListener 2 IoCs

pid	Process
616	WINWORD.EXE
616	WINWORD.EXE

Suspicious behavior: MapViewOfSection 1 IoCs

pid	Process
2296	Office_WorkForWestBank.exe

Suspicious use of SetWindowsHookEx 7 IoCs

pid	Process
616	WINWORD.EXE
616	WINWORD.EXE
616	WINWORD.EXE
616	WINWORD.EXE
616	WINWORD.EXE
616	WINWORD.EXE
616	WINWORD.EXE

Suspicious use of WriteProcessMemory 9 IoCs

description	pid	Process	procid_target
PID 616 wrote to memory of 1204	616	WINWORD.EXE	82
PID 616 wrote to memory of 1204	616	WINWORD.EXE	82
PID 1204 wrote to memory of 2296	1204	rundll32.exe	83
PID 1204 wrote to memory of 2296	1204	rundll32.exe	83
PID 1204 wrote to memory of 2296	1204	rundll32.exe	83
PID 2296 wrote to memory of 3524	2296	Office_WorkForWestBank.exe	84
PID 2296 wrote to memory of 3524	2296	Office_WorkForWestBank.exe	84
PID 2296 wrote to memory of 3524	2296	Office_WorkForWestBank.exe	84
PID 2296 wrote to memory of 3524	2296	Office_WorkForWestBank.exe	84

C:\Program Files\Microsoft Office\Root\Office16\WINWORD.EXE
"C:\Program Files\Microsoft Office\Root\Office16\WINWORD.EXE" /n "C:\Users\Admin\AppData\Local\Temp\Private document.docm" /o ""
1⤵
- Checks processor information in registry
- Enumerates system info in registry
- Suspicious behavior: AddClipboardFormatListener
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
PID:616
- C:\Windows\SYSTEM32\rundll32.exe
  rundll32 advpack.dll, RegisterOCX C:\ProgramData\Office_WorkForWestBank.exe
  2⤵
  - Process spawned unexpected child process
  - Suspicious use of WriteProcessMemory
  PID:1204
- - C:\ProgramData\Office_WorkForWestBank.exe
    C:\ProgramData\Office_WorkForWestBank.exe /RegServer
    3⤵
    - Executes dropped EXE
    - Loads dropped DLL
    - Suspicious use of SetThreadContext
    - Suspicious behavior: MapViewOfSection
    - Suspicious use of WriteProcessMemory
    PID:2296
  - - C:\ProgramData\Office_WorkForWestBank.exe
      C:\ProgramData\Office_WorkForWestBank.exe /RegServer
      4⤵
      Executes dropped EXE
      PID:3524

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Discovery

Query Registry

2

T1012

System Information Discovery

3

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

memory/616-5-0x00007FFE498B0000-0x00007FFE498C0000-memory.dmp

Filesize
64KB

Download
memory/616-6-0x00007FFE68CF0000-0x00007FFE69327000-memory.dmp

Filesize
6.2MB

Download
memory/616-2-0x00007FFE498B0000-0x00007FFE498C0000-memory.dmp

Filesize
64KB

Download
memory/616-4-0x00007FFE498B0000-0x00007FFE498C0000-memory.dmp

Filesize
64KB

Download
memory/616-3-0x00007FFE498B0000-0x00007FFE498C0000-memory.dmp

Filesize
64KB

Download
memory/3524-14-0x0000000040000000-0x000000004000A000-memory.dmp

Filesize
40KB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v6

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Downloads