buer | 4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1

General

Target

4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe
Size

2.0MB
MD5

a1c86dc81df8c629410fa9970423016e
SHA1

96bd00b2a79f00112e5f911019f140c95db19334
SHA256

4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1
SHA512

250b3b28e3e0dd15bdf1bc6443d1a6570d8ff917800b9e4d99b6c0f2d76361a7c4ec0a1b92ba19f9fa0f01399783d587445ae4e95e22c5f1d7aab0413ffabd3f

Score

10^/10

buer evasion loader persistence

Malware Config

Extracted

Family

buer

C2

http://bbload01.top/

http://bbload02.top/

Signatures

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

Modifies WinLogon for persistence 2 TTPs 1 IoCs

persistence

Winlogon Helper DLL

T1004

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\USER\S-1-5-21-1809750270-3141839489-3074374771-1000\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\ProgramData\\ErrorResponder\\errorResponder.exe\""	errorResponder.exe

Buer Loader 6 IoCs

Detects Buer loader in memory or disk.

loader

resource	yara_rule
behavioral2/memory/4324-132-0x000000003F220000-0x000000003F702000-memory.dmp	buer
behavioral2/memory/4324-133-0x000000003F220000-0x000000003F702000-memory.dmp	buer
behavioral2/memory/4324-134-0x000000003F220000-0x000000003F702000-memory.dmp	buer
behavioral2/memory/4324-137-0x000000003F220000-0x000000003F702000-memory.dmp	buer
behavioral2/memory/4612-142-0x000000003F260000-0x000000003F742000-memory.dmp	buer
behavioral2/memory/4612-143-0x000000003F260000-0x000000003F742000-memory.dmp	buer

Identifies VirtualBox via ACPI registry values (likely anti-VM) 2 TTPs 2 IoCs

evasion

Query Registry

T1012

Virtualization/Sandbox Evasion

T1497

description	ioc	Process
Key opened	\REGISTRY\MACHINE\HARDWARE\ACPI\DSDT\VBOX__	4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe
Key opened	\REGISTRY\MACHINE\HARDWARE\ACPI\DSDT\VBOX__	errorResponder.exe

Executes dropped EXE 1 IoCs

pid	Process
4612	errorResponder.exe

Checks BIOS information in registry 2 TTPs 4 IoCs

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

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\SystemBiosVersion	4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\VideoBiosVersion	4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\SystemBiosVersion	errorResponder.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\VideoBiosVersion	errorResponder.exe

Identifies Wine through registry keys 2 TTPs 2 IoCs

Wine is a compatibility layer capable of running Windows applications, which can be used as sandboxing environment.

evasion

Query Registry

T1012

Virtualization/Sandbox Evasion

T1497

description	ioc	Process
Key opened	\REGISTRY\USER\S-1-5-21-1809750270-3141839489-3074374771-1000\Software\Wine	4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe
Key opened	\REGISTRY\USER\S-1-5-21-1809750270-3141839489-3074374771-1000\Software\Wine	errorResponder.exe

Suspicious use of NtSetInformationThreadHideFromDebugger 2 IoCs

pid	Process
4324	4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe
4612	errorResponder.exe

Program crash 2 IoCs

pid	pid_target	Process	procid_target
4840	4608	WerFault.exe	94
1756	4608	WerFault.exe	94

Suspicious behavior: EnumeratesProcesses 6 IoCs

pid	Process
4324	4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe
4324	4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe
4612	errorResponder.exe
4612	errorResponder.exe
4612	errorResponder.exe
4612	errorResponder.exe

Suspicious use of WriteProcessMemory 15 IoCs

description	pid	Process	procid_target
PID 4324 wrote to memory of 4612	4324	4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe	93
PID 4324 wrote to memory of 4612	4324	4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe	93
PID 4324 wrote to memory of 4612	4324	4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe	93
PID 4612 wrote to memory of 4608	4612	errorResponder.exe	94
PID 4612 wrote to memory of 4608	4612	errorResponder.exe	94
PID 4612 wrote to memory of 4608	4612	errorResponder.exe	94
PID 4612 wrote to memory of 4608	4612	errorResponder.exe	94
PID 4612 wrote to memory of 4608	4612	errorResponder.exe	94
PID 4612 wrote to memory of 4608	4612	errorResponder.exe	94
PID 4612 wrote to memory of 4608	4612	errorResponder.exe	94
PID 4612 wrote to memory of 4608	4612	errorResponder.exe	94
PID 4612 wrote to memory of 4608	4612	errorResponder.exe	94
PID 4612 wrote to memory of 4608	4612	errorResponder.exe	94
PID 4612 wrote to memory of 4608	4612	errorResponder.exe	94
PID 4612 wrote to memory of 4608	4612	errorResponder.exe	94

C:\Users\Admin\AppData\Local\Temp\4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe
"C:\Users\Admin\AppData\Local\Temp\4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe"
1⤵
- Identifies VirtualBox via ACPI registry values (likely anti-VM)
- Checks BIOS information in registry
- Identifies Wine through registry keys
- Suspicious use of NtSetInformationThreadHideFromDebugger
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of WriteProcessMemory
PID:4324
- C:\ProgramData\ErrorResponder\errorResponder.exe
  C:\ProgramData\ErrorResponder\errorResponder.exe "C:\Users\Admin\AppData\Local\Temp\4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1.exe" ensgJJ
  2⤵
  - Modifies WinLogon for persistence
  - Identifies VirtualBox via ACPI registry values (likely anti-VM)
  - Executes dropped EXE
  - Checks BIOS information in registry
  - Identifies Wine through registry keys
  - Suspicious use of NtSetInformationThreadHideFromDebugger
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of WriteProcessMemory
  PID:4612
- - C:\Windows\SysWOW64\secinit.exe
    C:\ProgramData\ErrorResponder\errorResponder.exe
    3⤵
    PID:4608
  - - C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 4608 -s 272
      4⤵
      Program crash
      PID:4840
  - - C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 4608 -s 280
      4⤵
      Program crash
      PID:1756

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 376 -p 4608 -ip 4608
1⤵
PID:3364

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 536 -p 4608 -ip 4608
1⤵
PID:1724

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Winlogon Helper DLL

1

T1004

Privilege Escalation

Defense Evasion

Modify Registry

1

T1112

Virtualization/Sandbox Evasion

2

T1497

Credential Access

Discovery

Query Registry

3

T1012

System Information Discovery

1

T1082

Virtualization/Sandbox Evasion

2

T1497

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

C:\ProgramData\ErrorResponder\errorResponder.exe

Filesize
2.0MB

MD5
a1c86dc81df8c629410fa9970423016e

SHA1
96bd00b2a79f00112e5f911019f140c95db19334

SHA256
4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1

SHA512
250b3b28e3e0dd15bdf1bc6443d1a6570d8ff917800b9e4d99b6c0f2d76361a7c4ec0a1b92ba19f9fa0f01399783d587445ae4e95e22c5f1d7aab0413ffabd3f

Download Submit
C:\ProgramData\ErrorResponder\errorResponder.exe

Filesize
2.0MB

MD5
a1c86dc81df8c629410fa9970423016e

SHA1
96bd00b2a79f00112e5f911019f140c95db19334

SHA256
4ffe3bdfc6fe67298681315b83cef2513ad95b9b3e3162b9a5e3a27c44f26fe1

SHA512
250b3b28e3e0dd15bdf1bc6443d1a6570d8ff917800b9e4d99b6c0f2d76361a7c4ec0a1b92ba19f9fa0f01399783d587445ae4e95e22c5f1d7aab0413ffabd3f

Download Submit
memory/4324-138-0x00000000777E0000-0x0000000077983000-memory.dmp

Filesize
1.6MB

Download
memory/4324-134-0x000000003F220000-0x000000003F702000-memory.dmp

Filesize
4.9MB

Download
memory/4324-132-0x000000003F220000-0x000000003F702000-memory.dmp

Filesize
4.9MB

Download
memory/4324-137-0x000000003F220000-0x000000003F702000-memory.dmp

Filesize
4.9MB

Download
memory/4324-130-0x000000003F220000-0x000000003F702000-memory.dmp

Filesize
4.9MB

Download
memory/4324-133-0x000000003F220000-0x000000003F702000-memory.dmp

Filesize
4.9MB

Download
memory/4324-131-0x00000000777E0000-0x0000000077983000-memory.dmp

Filesize
1.6MB

Download
memory/4608-145-0x0000000000CE0000-0x00000000011C2000-memory.dmp

Filesize
4.9MB

Download
memory/4612-139-0x000000003F260000-0x000000003F742000-memory.dmp

Filesize
4.9MB

Download
memory/4612-142-0x000000003F260000-0x000000003F742000-memory.dmp

Filesize
4.9MB

Download
memory/4612-143-0x000000003F260000-0x000000003F742000-memory.dmp

Filesize
4.9MB

Download
memory/4612-141-0x00000000777E0000-0x0000000077983000-memory.dmp

Filesize
1.6MB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v6

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Downloads