buer | ba5fa7cc1a918b866354f4a5d9d92ceb3965ff81eb96e1608f190bccf12d38e6

General

Target

ba5fa7cc1a918b866354f4a5d9d92ceb3965ff81eb96e1608f190bccf12d38e6.exe
Size

89KB
MD5

96f008e97e84f07d643548ca503d7930
SHA1

7f0d5571b331b681e1689a2fda251329dcfa527f
SHA256

ba5fa7cc1a918b866354f4a5d9d92ceb3965ff81eb96e1608f190bccf12d38e6
SHA512

55633a88d52c46e286153c94698ec6fad8d7ecfe1d0cd48873117f9dca9f8b6681236e07a1f3d827ed57bbc7b4758060a4482d30b21cc52119680a8e603d3b64

Score

10^/10

buer loader persistence

Malware Config

Extracted

Family

buer

C2

https://syndicationtwimg.site/

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-1-5-21-2329389628-4064185017-3901522362-1000\Software\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\ProgramData\\3c74a785e11087856a25\\gennt.exe\""	gennt.exe

Buer Loader 2 IoCs

Detects Buer loader in memory or disk.

resource	yara_rule
behavioral1/memory/736-59-0x0000000000270000-0x000000000027C000-memory.dmp	buer
behavioral1/memory/1608-64-0x0000000000280000-0x000000000028C000-memory.dmp	buer

Executes dropped EXE 1 IoCs

pid	Process
1608	gennt.exe

Deletes itself 1 IoCs

pid	Process
1608	gennt.exe

Loads dropped DLL 2 IoCs

pid	Process
736	ba5fa7cc1a918b866354f4a5d9d92ceb3965ff81eb96e1608f190bccf12d38e6.exe
736	ba5fa7cc1a918b866354f4a5d9d92ceb3965ff81eb96e1608f190bccf12d38e6.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)	\??\B:	gennt.exe
File opened (read-only)	\??\E:	gennt.exe
File opened (read-only)	\??\H:	gennt.exe
File opened (read-only)	\??\W:	gennt.exe
File opened (read-only)	\??\A:	gennt.exe
File opened (read-only)	\??\O:	gennt.exe
File opened (read-only)	\??\X:	gennt.exe
File opened (read-only)	\??\F:	gennt.exe
File opened (read-only)	\??\I:	gennt.exe
File opened (read-only)	\??\J:	gennt.exe
File opened (read-only)	\??\M:	gennt.exe
File opened (read-only)	\??\N:	gennt.exe
File opened (read-only)	\??\P:	gennt.exe
File opened (read-only)	\??\Q:	gennt.exe
File opened (read-only)	\??\R:	gennt.exe
File opened (read-only)	\??\S:	gennt.exe
File opened (read-only)	\??\T:	gennt.exe
File opened (read-only)	\??\V:	gennt.exe
File opened (read-only)	\??\Y:	gennt.exe
File opened (read-only)	\??\G:	gennt.exe
File opened (read-only)	\??\K:	gennt.exe
File opened (read-only)	\??\L:	gennt.exe
File opened (read-only)	\??\U:	gennt.exe
File opened (read-only)	\??\Z:	gennt.exe

Suspicious behavior: EnumeratesProcesses 1 IoCs

pid	Process
1608	gennt.exe

Suspicious use of WriteProcessMemory 8 IoCs

description	pid	Process	procid_target
PID 736 wrote to memory of 1608	736	ba5fa7cc1a918b866354f4a5d9d92ceb3965ff81eb96e1608f190bccf12d38e6.exe	27
PID 736 wrote to memory of 1608	736	ba5fa7cc1a918b866354f4a5d9d92ceb3965ff81eb96e1608f190bccf12d38e6.exe	27
PID 736 wrote to memory of 1608	736	ba5fa7cc1a918b866354f4a5d9d92ceb3965ff81eb96e1608f190bccf12d38e6.exe	27
PID 736 wrote to memory of 1608	736	ba5fa7cc1a918b866354f4a5d9d92ceb3965ff81eb96e1608f190bccf12d38e6.exe	27
PID 1608 wrote to memory of 588	1608	gennt.exe	28
PID 1608 wrote to memory of 588	1608	gennt.exe	28
PID 1608 wrote to memory of 588	1608	gennt.exe	28
PID 1608 wrote to memory of 588	1608	gennt.exe	28

C:\Users\Admin\AppData\Local\Temp\ba5fa7cc1a918b866354f4a5d9d92ceb3965ff81eb96e1608f190bccf12d38e6.exe
"C:\Users\Admin\AppData\Local\Temp\ba5fa7cc1a918b866354f4a5d9d92ceb3965ff81eb96e1608f190bccf12d38e6.exe"
1⤵
- Loads dropped DLL
- Suspicious use of WriteProcessMemory
PID:736
- C:\ProgramData\3c74a785e11087856a25\gennt.exe
  C:\ProgramData\3c74a785e11087856a25\gennt.exe "C:\Users\Admin\AppData\Local\Temp\ba5fa7cc1a918b866354f4a5d9d92ceb3965ff81eb96e1608f190bccf12d38e6.exe" ensgJJ
  2⤵
  - Modifies WinLogon for persistence
  - Executes dropped EXE
  - Deletes itself
  - Enumerates connected drives
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of WriteProcessMemory
  PID:1608
- - C:\Windows\SysWOW64\secinit.exe
    C:\ProgramData\3c74a785e11087856a25\gennt.exe
    3⤵
    PID:588

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

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Downloads

memory/736-54-0x0000000076B81000-0x0000000076B83000-memory.dmp

Filesize
8KB

Download
memory/736-58-0x0000000000400000-0x0000000000418000-memory.dmp

Filesize
96KB

Download
memory/736-59-0x0000000000270000-0x000000000027C000-memory.dmp

Filesize
48KB

Download
memory/1608-62-0x0000000000400000-0x0000000000418000-memory.dmp

Filesize
96KB

Download
memory/1608-63-0x0000000000240000-0x0000000000241000-memory.dmp

Filesize
4KB

Download
memory/1608-64-0x0000000000280000-0x000000000028C000-memory.dmp

Filesize
48KB

Download

Analysis

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