buer | 9e746625abad522321067f546c40e8b26176ef5585bf3a45cb58ff758738f68c

General

Target

newbuer.exe
Size

111KB
MD5

4df84f8de8a5526f119c26518b529757
SHA1

42d281abeb10649bff097504f20e8fc2c8e85f5c
SHA256

9e746625abad522321067f546c40e8b26176ef5585bf3a45cb58ff758738f68c
SHA512

68cd6ce9eb7f01d7e6b2b2fff6dfdf981834168cb406a7d67df1f4c9d78b36b22689b03e408e3e68faf76d3bb4b0abd109024d4e2389258ea64a89f54e4a4b88

Score

10^/10

buer loader persistence

Malware Config

Extracted

Family

buer

C2

https://maldivosgrant.net/

https://jokenoiam.net/

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-1-5-21-910373003-3952921535-3480519689-1000\Software\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\ProgramData\\RedTools\\networker.exe\""	networker.exe

Buer Loader 2 IoCs

Detects Buer loader in memory or disk.

resource	yara_rule
behavioral1/memory/112-1-0x0000000040000000-0x000000004000C000-memory.dmp	buer
behavioral1/memory/112-2-0x0000000040000000-0x000000004000C000-memory.dmp	buer

Executes dropped EXE 2 IoCs

pid	Process
1836	networker.exe
1788	networker.exe

Deletes itself 1 IoCs

pid	Process
1788	networker.exe

Loads dropped DLL 3 IoCs

pid	Process
288	newbuer.exe
112	newbuer.exe
1836	networker.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)	\??\M:	networker.exe
File opened (read-only)	\??\P:	networker.exe
File opened (read-only)	\??\T:	networker.exe
File opened (read-only)	\??\U:	networker.exe
File opened (read-only)	\??\W:	networker.exe
File opened (read-only)	\??\V:	networker.exe
File opened (read-only)	\??\Y:	networker.exe
File opened (read-only)	\??\G:	networker.exe
File opened (read-only)	\??\I:	networker.exe
File opened (read-only)	\??\J:	networker.exe
File opened (read-only)	\??\L:	networker.exe
File opened (read-only)	\??\O:	networker.exe
File opened (read-only)	\??\S:	networker.exe
File opened (read-only)	\??\Z:	networker.exe
File opened (read-only)	\??\B:	networker.exe
File opened (read-only)	\??\H:	networker.exe
File opened (read-only)	\??\K:	networker.exe
File opened (read-only)	\??\Q:	networker.exe
File opened (read-only)	\??\R:	networker.exe
File opened (read-only)	\??\A:	networker.exe
File opened (read-only)	\??\E:	networker.exe
File opened (read-only)	\??\F:	networker.exe
File opened (read-only)	\??\N:	networker.exe
File opened (read-only)	\??\X:	networker.exe

Suspicious use of SetThreadContext 2 IoCs

description	pid	Process	procid_target
PID 288 set thread context of 112	288	newbuer.exe	24
PID 1836 set thread context of 1788	1836	networker.exe	28

Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s). Likely ransomware behaviour.

System Information Discovery
T1082

NSIS installer 8 IoCs

installer

resource	yara_rule
behavioral1/files/0x00030000000131a3-3.dat	nsis_installer_1
behavioral1/files/0x00030000000131a3-3.dat	nsis_installer_2
behavioral1/files/0x00030000000131a3-4.dat	nsis_installer_1
behavioral1/files/0x00030000000131a3-4.dat	nsis_installer_2
behavioral1/files/0x00030000000131a3-5.dat	nsis_installer_1
behavioral1/files/0x00030000000131a3-5.dat	nsis_installer_2
behavioral1/files/0x00030000000131a3-8.dat	nsis_installer_1
behavioral1/files/0x00030000000131a3-8.dat	nsis_installer_2

Suspicious behavior: EnumeratesProcesses 1 IoCs

pid	Process
1788	networker.exe

Suspicious behavior: MapViewOfSection 2 IoCs

pid	Process
288	newbuer.exe
1836	networker.exe

Suspicious use of WriteProcessMemory 18 IoCs

description	pid	Process	procid_target
PID 288 wrote to memory of 112	288	newbuer.exe	24
PID 288 wrote to memory of 112	288	newbuer.exe	24
PID 288 wrote to memory of 112	288	newbuer.exe	24
PID 288 wrote to memory of 112	288	newbuer.exe	24
PID 288 wrote to memory of 112	288	newbuer.exe	24
PID 112 wrote to memory of 1836	112	newbuer.exe	27
PID 112 wrote to memory of 1836	112	newbuer.exe	27
PID 112 wrote to memory of 1836	112	newbuer.exe	27
PID 112 wrote to memory of 1836	112	newbuer.exe	27
PID 1836 wrote to memory of 1788	1836	networker.exe	28
PID 1836 wrote to memory of 1788	1836	networker.exe	28
PID 1836 wrote to memory of 1788	1836	networker.exe	28
PID 1836 wrote to memory of 1788	1836	networker.exe	28
PID 1836 wrote to memory of 1788	1836	networker.exe	28
PID 1788 wrote to memory of 1784	1788	networker.exe	29
PID 1788 wrote to memory of 1784	1788	networker.exe	29
PID 1788 wrote to memory of 1784	1788	networker.exe	29
PID 1788 wrote to memory of 1784	1788	networker.exe	29

C:\Users\Admin\AppData\Local\Temp\newbuer.exe
"C:\Users\Admin\AppData\Local\Temp\newbuer.exe"
1⤵
- Loads dropped DLL
- Suspicious use of SetThreadContext
- Suspicious behavior: MapViewOfSection
- Suspicious use of WriteProcessMemory
PID:288
- C:\Users\Admin\AppData\Local\Temp\newbuer.exe
  "C:\Users\Admin\AppData\Local\Temp\newbuer.exe"
  2⤵
  - Loads dropped DLL
  - Suspicious use of WriteProcessMemory
  PID:112
- - C:\ProgramData\RedTools\networker.exe
    C:\ProgramData\RedTools\networker.exe "C:\Users\Admin\AppData\Local\Temp\newbuer.exe" ensgJJ
    3⤵
    - Executes dropped EXE
    - Loads dropped DLL
    - Suspicious use of SetThreadContext
    - Suspicious behavior: MapViewOfSection
    - Suspicious use of WriteProcessMemory
    PID:1836
  - - C:\ProgramData\RedTools\networker.exe
      C:\ProgramData\RedTools\networker.exe "C:\Users\Admin\AppData\Local\Temp\newbuer.exe" ensgJJ
      4⤵
      Modifies WinLogon for persistence
      Executes dropped EXE
      Deletes itself
      Enumerates connected drives
      Suspicious behavior: EnumeratesProcesses
      Suspicious use of WriteProcessMemory
      PID:1788
    - - C:\Windows\SysWOW64\secinit.exe
        
        C:\ProgramData\RedTools\networker.exe
        5⤵
        
        PID:1784

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

2

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

Replay Monitor

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Downloads

memory/112-1-0x0000000040000000-0x000000004000C000-memory.dmp

Filesize
48KB

Download
memory/112-2-0x0000000040000000-0x000000004000C000-memory.dmp

Filesize
48KB

Download

Analysis

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