buer | 2ab0259da85215561573043bdec94b68e0e2cf391de21ef69f5f03b16020fe62

General

Target

214053f.bin.exe
Size

38KB
MD5

1f4ce9581d372c6297794233cbeca1ea
SHA1

c9661c46db129433e350d1ca3fd0ebd79b190f88
SHA256

f23db00ee052d07bf66ce6aa644ead488e182dfb21c4c5c42bb9677db839a310
SHA512

571c4a811586bf26b3de8cbcc59be0b27f4fb58826844e8ef73dcf8c61af8c918dd8c06f42339867b4877f00ab11e8ec8d1901afbde57e967748ccd23425447f

Score

10^/10

buer loader persistence

Malware Config

Extracted

Family

buer

C2

https://162.244.81.87/

http://162.244.81.87:8080/

Signatures

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

Modifies WinLogon for persistence 2 TTPs 2 IoCs

persistence

Winlogon Helper DLL

T1004

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\ProgramData\\29ff734d026e5d3a89a0\\gennt.exe\""	gennt.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\ProgramData\\29ff734d026e5d3a89a0\\gennt.exe\""	secinit.exe

Buer Loader 4 IoCs

Detects Buer loader in memory or disk.

resource	yara_rule
behavioral2/files/0x000300000001a2e0-115.dat	buer
behavioral2/files/0x000300000001a2e0-116.dat	buer
behavioral2/memory/3792-117-0x0000000000000000-mapping.dmp	buer
behavioral2/memory/3792-119-0x0000000000940000-0x000000000094C000-memory.dmp	buer

Executes dropped EXE 1 IoCs

pid	Process
3812	gennt.exe

Deletes itself 1 IoCs

pid	Process
3812	gennt.exe

Enumerates connected drives 3 TTPs 24 IoCs

Attempts to read the root path of hard drives other than the default C: drive.

Query Registry

T1012

Peripheral Device Discovery

T1120

System Information Discovery

T1082

description	ioc	Process
File opened (read-only)	\??\F:	secinit.exe
File opened (read-only)	\??\H:	secinit.exe
File opened (read-only)	\??\T:	secinit.exe
File opened (read-only)	\??\W:	secinit.exe
File opened (read-only)	\??\O:	secinit.exe
File opened (read-only)	\??\P:	secinit.exe
File opened (read-only)	\??\S:	secinit.exe
File opened (read-only)	\??\Y:	secinit.exe
File opened (read-only)	\??\B:	secinit.exe
File opened (read-only)	\??\E:	secinit.exe
File opened (read-only)	\??\G:	secinit.exe
File opened (read-only)	\??\K:	secinit.exe
File opened (read-only)	\??\X:	secinit.exe
File opened (read-only)	\??\A:	secinit.exe
File opened (read-only)	\??\I:	secinit.exe
File opened (read-only)	\??\J:	secinit.exe
File opened (read-only)	\??\R:	secinit.exe
File opened (read-only)	\??\U:	secinit.exe
File opened (read-only)	\??\V:	secinit.exe
File opened (read-only)	\??\Z:	secinit.exe
File opened (read-only)	\??\L:	secinit.exe
File opened (read-only)	\??\M:	secinit.exe
File opened (read-only)	\??\N:	secinit.exe
File opened (read-only)	\??\Q:	secinit.exe

Suspicious behavior: EnumeratesProcesses 2 IoCs

pid	Process
3792	secinit.exe
3792	secinit.exe

Suspicious use of WriteProcessMemory 16 IoCs

description	pid	Process	procid_target
PID 3972 wrote to memory of 3812	3972	214053f.bin.exe	78
PID 3972 wrote to memory of 3812	3972	214053f.bin.exe	78
PID 3972 wrote to memory of 3812	3972	214053f.bin.exe	78
PID 3812 wrote to memory of 3792	3812	gennt.exe	79
PID 3812 wrote to memory of 3792	3812	gennt.exe	79
PID 3812 wrote to memory of 3792	3812	gennt.exe	79
PID 3812 wrote to memory of 3792	3812	gennt.exe	79
PID 3812 wrote to memory of 3792	3812	gennt.exe	79
PID 3812 wrote to memory of 3792	3812	gennt.exe	79
PID 3812 wrote to memory of 3792	3812	gennt.exe	79
PID 3812 wrote to memory of 3792	3812	gennt.exe	79
PID 3812 wrote to memory of 3792	3812	gennt.exe	79
PID 3812 wrote to memory of 3792	3812	gennt.exe	79
PID 3792 wrote to memory of 3692	3792	secinit.exe	80
PID 3792 wrote to memory of 3692	3792	secinit.exe	80
PID 3792 wrote to memory of 3692	3792	secinit.exe	80

C:\Users\Admin\AppData\Local\Temp\214053f.bin.exe
"C:\Users\Admin\AppData\Local\Temp\214053f.bin.exe"
1⤵
- Suspicious use of WriteProcessMemory
PID:3972
- C:\ProgramData\29ff734d026e5d3a89a0\gennt.exe
  C:\ProgramData\29ff734d026e5d3a89a0\gennt.exe "C:\Users\Admin\AppData\Local\Temp\214053f.bin.exe" ensgJJ
  2⤵
  - Modifies WinLogon for persistence
  - Executes dropped EXE
  - Deletes itself
  - Suspicious use of WriteProcessMemory
  PID:3812
- - C:\Windows\SysWOW64\secinit.exe
    C:\ProgramData\29ff734d026e5d3a89a0\gennt.exe
    3⤵
    - Modifies WinLogon for persistence
    - Enumerates connected drives
    - Suspicious behavior: EnumeratesProcesses
    - Suspicious use of WriteProcessMemory
    PID:3792
  - - C:\Windows\SysWOW64\cmd.exe
      "C:\Windows\System32\cmd.exe" powershell.exe -Command "& {Add-MpPreference -ExclusionPath C:\ProgramData\29ff734d026e5d3a89a0}"
      4⤵
      PID:3692

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Winlogon Helper DLL

1

T1004

Privilege Escalation

Defense Evasion

Modify Registry

1

T1112

Credential Access

Discovery

Peripheral Device Discovery

Query Registry

System Information Discovery

1

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

Replay Monitor

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Downloads

memory/3792-118-0x0000000000950000-0x0000000000951000-memory.dmp

Filesize
4KB

Download
memory/3792-119-0x0000000000940000-0x000000000094C000-memory.dmp

Filesize
48KB

Download

Analysis

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