buer | 44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2

General

Target

44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.exe
Size

1.8MB
MD5

12879fe44a82eb3491d7e04ed821a740
SHA1

8984616aade39197467c89cb08b1b42345acbed4
SHA256

44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2
SHA512

8110746c6db6169a836d5f8c2f231a6b862cf878b9c1af5625770cb050fa86b2efa64614313783deb3d26f6533f90ed284a158b9f97f139cd920c715a07cb6b6

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 7 IoCs

Detects Buer loader in memory or disk.

loader

resource	yara_rule
behavioral2/memory/4476-132-0x000000003F030000-0x000000003F48E000-memory.dmp	buer
behavioral2/memory/4476-133-0x000000003F030000-0x000000003F48E000-memory.dmp	buer
behavioral2/memory/4476-134-0x000000003F030000-0x000000003F48E000-memory.dmp	buer
behavioral2/memory/4476-137-0x000000003F030000-0x000000003F48E000-memory.dmp	buer
behavioral2/memory/3248-142-0x000000003F740000-0x000000003FB9E000-memory.dmp	buer
behavioral2/memory/3248-143-0x000000003F740000-0x000000003FB9E000-memory.dmp	buer
behavioral2/memory/3248-144-0x000000003F740000-0x000000003FB9E000-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__	44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.exe
Key opened	\REGISTRY\MACHINE\HARDWARE\ACPI\DSDT\VBOX__	errorResponder.exe

Executes dropped EXE 1 IoCs

pid	Process
3248	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	44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\VideoBiosVersion	44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.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	44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.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
4476	44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.exe
3248	errorResponder.exe

Program crash 2 IoCs

pid	pid_target	Process	procid_target
1420	2668	WerFault.exe	88
2316	2668	WerFault.exe	88

Suspicious behavior: EnumeratesProcesses 6 IoCs

pid	Process
4476	44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.exe
4476	44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.exe
3248	errorResponder.exe
3248	errorResponder.exe
3248	errorResponder.exe
3248	errorResponder.exe

Suspicious use of WriteProcessMemory 15 IoCs

description	pid	Process	procid_target
PID 4476 wrote to memory of 3248	4476	44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.exe	87
PID 4476 wrote to memory of 3248	4476	44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.exe	87
PID 4476 wrote to memory of 3248	4476	44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.exe	87
PID 3248 wrote to memory of 2668	3248	errorResponder.exe	88
PID 3248 wrote to memory of 2668	3248	errorResponder.exe	88
PID 3248 wrote to memory of 2668	3248	errorResponder.exe	88
PID 3248 wrote to memory of 2668	3248	errorResponder.exe	88
PID 3248 wrote to memory of 2668	3248	errorResponder.exe	88
PID 3248 wrote to memory of 2668	3248	errorResponder.exe	88
PID 3248 wrote to memory of 2668	3248	errorResponder.exe	88
PID 3248 wrote to memory of 2668	3248	errorResponder.exe	88
PID 3248 wrote to memory of 2668	3248	errorResponder.exe	88
PID 3248 wrote to memory of 2668	3248	errorResponder.exe	88
PID 3248 wrote to memory of 2668	3248	errorResponder.exe	88
PID 3248 wrote to memory of 2668	3248	errorResponder.exe	88

C:\Users\Admin\AppData\Local\Temp\44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.exe
"C:\Users\Admin\AppData\Local\Temp\44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.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:4476
- C:\ProgramData\ErrorResponder\errorResponder.exe
  C:\ProgramData\ErrorResponder\errorResponder.exe "C:\Users\Admin\AppData\Local\Temp\44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2.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:3248
- - C:\Windows\SysWOW64\secinit.exe
    C:\ProgramData\ErrorResponder\errorResponder.exe
    3⤵
    PID:2668
  - - C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 2668 -s 272
      4⤵
      Program crash
      PID:1420
  - - C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 2668 -s 280
      4⤵
      Program crash
      PID:2316

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 408 -p 2668 -ip 2668
1⤵
PID:2916

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 512 -p 2668 -ip 2668
1⤵
PID:1988

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
1.8MB

MD5
12879fe44a82eb3491d7e04ed821a740

SHA1
8984616aade39197467c89cb08b1b42345acbed4

SHA256
44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2

SHA512
8110746c6db6169a836d5f8c2f231a6b862cf878b9c1af5625770cb050fa86b2efa64614313783deb3d26f6533f90ed284a158b9f97f139cd920c715a07cb6b6

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

Filesize
1.8MB

MD5
12879fe44a82eb3491d7e04ed821a740

SHA1
8984616aade39197467c89cb08b1b42345acbed4

SHA256
44ecc8efe07d1908dad842bd31f0aa15bb8810401829bc0b3383e2c0d9750bd2

SHA512
8110746c6db6169a836d5f8c2f231a6b862cf878b9c1af5625770cb050fa86b2efa64614313783deb3d26f6533f90ed284a158b9f97f139cd920c715a07cb6b6

Download Submit
memory/2668-146-0x00000000010C0000-0x000000000151E000-memory.dmp

Filesize
4.4MB

Download
memory/3248-144-0x000000003F740000-0x000000003FB9E000-memory.dmp

Filesize
4.4MB

Download
memory/3248-143-0x000000003F740000-0x000000003FB9E000-memory.dmp

Filesize
4.4MB

Download
memory/3248-142-0x000000003F740000-0x000000003FB9E000-memory.dmp

Filesize
4.4MB

Download
memory/3248-141-0x00000000778E0000-0x0000000077A83000-memory.dmp

Filesize
1.6MB

Download
memory/3248-139-0x000000003F740000-0x000000003FB9E000-memory.dmp

Filesize
4.4MB

Download
memory/4476-134-0x000000003F030000-0x000000003F48E000-memory.dmp

Filesize
4.4MB

Download
memory/4476-138-0x00000000778E0000-0x0000000077A83000-memory.dmp

Filesize
1.6MB

Download
memory/4476-137-0x000000003F030000-0x000000003F48E000-memory.dmp

Filesize
4.4MB

Download
memory/4476-130-0x000000003F030000-0x000000003F48E000-memory.dmp

Filesize
4.4MB

Download
memory/4476-133-0x000000003F030000-0x000000003F48E000-memory.dmp

Filesize
4.4MB

Download
memory/4476-132-0x000000003F030000-0x000000003F48E000-memory.dmp

Filesize
4.4MB

Download
memory/4476-131-0x00000000778E0000-0x0000000077A83000-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