buer | f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3

General

Target

f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.exe
Size

1.7MB
MD5

85851bc9cecff7ec618e498f2f52ab5a
SHA1

21f4efb62167f1e9b4f82d41ba3d09b58856f201
SHA256

f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3
SHA512

c6cac25fd43ff4d821f991c19ecf47a2f8dcf66fdbff1ce377611093b7db925b0587bd15db23061bd03ae1ad380c6362c644734a5f6ae0e3e723c1500c62813f

Score

10^/10

buer evasion loader persistence

Malware Config

Extracted

Family

buer

C2

http://kload01.info/

http://kload02.info/

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\\UBlockPlugin\\plugin.exe\""	plugin.exe

Buer Loader 7 IoCs

Detects Buer loader in memory or disk.

loader

resource	yara_rule
behavioral2/memory/4284-132-0x000000003F580000-0x000000003F9D4000-memory.dmp	buer
behavioral2/memory/4284-133-0x000000003F580000-0x000000003F9D4000-memory.dmp	buer
behavioral2/memory/4284-135-0x000000003F580000-0x000000003F9D4000-memory.dmp	buer
behavioral2/memory/4284-139-0x000000003F580000-0x000000003F9D4000-memory.dmp	buer
behavioral2/memory/1016-142-0x000000003F5F0000-0x000000003FA44000-memory.dmp	buer
behavioral2/memory/1016-143-0x000000003F5F0000-0x000000003FA44000-memory.dmp	buer
behavioral2/memory/1016-144-0x000000003F5F0000-0x000000003FA44000-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__	f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.exe
Key opened	\REGISTRY\MACHINE\HARDWARE\ACPI\DSDT\VBOX__	plugin.exe

Executes dropped EXE 1 IoCs

pid	Process
1016	plugin.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	plugin.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\VideoBiosVersion	plugin.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\SystemBiosVersion	f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\VideoBiosVersion	f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.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	f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.exe
Key opened	\REGISTRY\USER\S-1-5-21-1809750270-3141839489-3074374771-1000\Software\Wine	plugin.exe

Suspicious use of NtSetInformationThreadHideFromDebugger 2 IoCs

pid	Process
4284	f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.exe
1016	plugin.exe

Program crash 1 IoCs

pid	pid_target	Process	procid_target
384	5044	WerFault.exe	91

Suspicious behavior: EnumeratesProcesses 6 IoCs

pid	Process
4284	f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.exe
4284	f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.exe
1016	plugin.exe
1016	plugin.exe
1016	plugin.exe
1016	plugin.exe

Suspicious use of WriteProcessMemory 15 IoCs

description	pid	Process	procid_target
PID 4284 wrote to memory of 1016	4284	f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.exe	90
PID 4284 wrote to memory of 1016	4284	f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.exe	90
PID 4284 wrote to memory of 1016	4284	f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.exe	90
PID 1016 wrote to memory of 5044	1016	plugin.exe	91
PID 1016 wrote to memory of 5044	1016	plugin.exe	91
PID 1016 wrote to memory of 5044	1016	plugin.exe	91
PID 1016 wrote to memory of 5044	1016	plugin.exe	91
PID 1016 wrote to memory of 5044	1016	plugin.exe	91
PID 1016 wrote to memory of 5044	1016	plugin.exe	91
PID 1016 wrote to memory of 5044	1016	plugin.exe	91
PID 1016 wrote to memory of 5044	1016	plugin.exe	91
PID 1016 wrote to memory of 5044	1016	plugin.exe	91
PID 1016 wrote to memory of 5044	1016	plugin.exe	91
PID 1016 wrote to memory of 5044	1016	plugin.exe	91
PID 1016 wrote to memory of 5044	1016	plugin.exe	91

C:\Users\Admin\AppData\Local\Temp\f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.exe
"C:\Users\Admin\AppData\Local\Temp\f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.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:4284
- C:\ProgramData\UBlockPlugin\plugin.exe
  C:\ProgramData\UBlockPlugin\plugin.exe "C:\Users\Admin\AppData\Local\Temp\f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3.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:1016
- - C:\Windows\SysWOW64\secinit.exe
    C:\ProgramData\UBlockPlugin\plugin.exe
    3⤵
    PID:5044
  - - C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 5044 -s 220
      4⤵
      Program crash
      PID:384

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 408 -p 5044 -ip 5044
1⤵
PID:4880

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\UBlockPlugin\plugin.exe

Filesize
1.7MB

MD5
85851bc9cecff7ec618e498f2f52ab5a

SHA1
21f4efb62167f1e9b4f82d41ba3d09b58856f201

SHA256
f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3

SHA512
c6cac25fd43ff4d821f991c19ecf47a2f8dcf66fdbff1ce377611093b7db925b0587bd15db23061bd03ae1ad380c6362c644734a5f6ae0e3e723c1500c62813f

Download Submit
C:\ProgramData\UBlockPlugin\plugin.exe

Filesize
1.7MB

MD5
85851bc9cecff7ec618e498f2f52ab5a

SHA1
21f4efb62167f1e9b4f82d41ba3d09b58856f201

SHA256
f73cf8983ba1581437ef86a24e97cde0929d9ee8d5224a834ab55353cb0fb5f3

SHA512
c6cac25fd43ff4d821f991c19ecf47a2f8dcf66fdbff1ce377611093b7db925b0587bd15db23061bd03ae1ad380c6362c644734a5f6ae0e3e723c1500c62813f

Download Submit
memory/1016-142-0x000000003F5F0000-0x000000003FA44000-memory.dmp

Filesize
4.3MB

Download
memory/1016-141-0x00000000770F0000-0x0000000077293000-memory.dmp

Filesize
1.6MB

Download
memory/1016-144-0x000000003F5F0000-0x000000003FA44000-memory.dmp

Filesize
4.3MB

Download
memory/1016-143-0x000000003F5F0000-0x000000003FA44000-memory.dmp

Filesize
4.3MB

Download
memory/4284-139-0x000000003F580000-0x000000003F9D4000-memory.dmp

Filesize
4.3MB

Download
memory/4284-131-0x00000000770F0000-0x0000000077293000-memory.dmp

Filesize
1.6MB

Download
memory/4284-133-0x000000003F580000-0x000000003F9D4000-memory.dmp

Filesize
4.3MB

Download
memory/4284-140-0x00000000770F0000-0x0000000077293000-memory.dmp

Filesize
1.6MB

Download
memory/4284-132-0x000000003F580000-0x000000003F9D4000-memory.dmp

Filesize
4.3MB

Download
memory/4284-130-0x000000003F580000-0x000000003F9D4000-memory.dmp

Filesize
4.3MB

Download
memory/4284-135-0x000000003F580000-0x000000003F9D4000-memory.dmp

Filesize
4.3MB

Download
memory/4284-134-0x00000000770F0000-0x0000000077293000-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