buer | 4aba8ea34e057b8239ff29028fa3ab829f53b2861d84a44fa9857b7d96e3a403

General

Target

4aba8ea34e057b8239ff29028fa3ab829f53b2861d84a44fa9857b7d96e3a403.exe
Size

182KB
MD5

87ad62ff5669b41f8994695b3aa05cbf
SHA1

c6eb9d9a0df8ca97784b57ebe719b227ebfaf262
SHA256

4aba8ea34e057b8239ff29028fa3ab829f53b2861d84a44fa9857b7d96e3a403
SHA512

2b728b84f8377f407e293e723c5bb7813320e371d4e604323ddb397f418a367df8d925ac7d69dd53137df67f8d5b460f730f19cb94949dd14ab37da170cc47fd

Score

10^/10

buer loader persistence

Malware Config

Extracted

Family

buer

C2

https://gstatiknetiplist.cc/

https://gstatiknetiplist.com/

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-1-5-21-1081944012-3634099177-1681222835-1000\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\ProgramData\\ErrorResponder\\responder.exe\""	responder.exe

Buer Loader 3 IoCs

Detects Buer loader in memory or disk.

loader

resource	yara_rule
behavioral2/memory/1928-131-0x0000000000030000-0x000000000003A000-memory.dmp	buer
behavioral2/memory/1928-132-0x0000000040000000-0x00000000429E4000-memory.dmp	buer
behavioral2/memory/3784-137-0x0000000040000000-0x00000000429E4000-memory.dmp	buer

Executes dropped EXE 1 IoCs

pid	Process
3784	responder.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)	\??\S:	responder.exe
File opened (read-only)	\??\W:	responder.exe
File opened (read-only)	\??\Z:	responder.exe
File opened (read-only)	\??\E:	responder.exe
File opened (read-only)	\??\F:	responder.exe
File opened (read-only)	\??\I:	responder.exe
File opened (read-only)	\??\L:	responder.exe
File opened (read-only)	\??\N:	responder.exe
File opened (read-only)	\??\O:	responder.exe
File opened (read-only)	\??\Y:	responder.exe
File opened (read-only)	\??\A:	responder.exe
File opened (read-only)	\??\J:	responder.exe
File opened (read-only)	\??\R:	responder.exe
File opened (read-only)	\??\T:	responder.exe
File opened (read-only)	\??\U:	responder.exe
File opened (read-only)	\??\X:	responder.exe
File opened (read-only)	\??\Q:	responder.exe
File opened (read-only)	\??\V:	responder.exe
File opened (read-only)	\??\B:	responder.exe
File opened (read-only)	\??\G:	responder.exe
File opened (read-only)	\??\H:	responder.exe
File opened (read-only)	\??\K:	responder.exe
File opened (read-only)	\??\M:	responder.exe
File opened (read-only)	\??\P:	responder.exe

Program crash 2 IoCs

pid	pid_target	Process	procid_target
4832	1928	WerFault.exe	79
3912	116	WerFault.exe	91

Suspicious behavior: EnumeratesProcesses 2 IoCs

pid	Process
3784	responder.exe
3784	responder.exe

Suspicious use of WriteProcessMemory 13 IoCs

description	pid	Process	procid_target
PID 1928 wrote to memory of 3784	1928	4aba8ea34e057b8239ff29028fa3ab829f53b2861d84a44fa9857b7d96e3a403.exe	88
PID 1928 wrote to memory of 3784	1928	4aba8ea34e057b8239ff29028fa3ab829f53b2861d84a44fa9857b7d96e3a403.exe	88
PID 1928 wrote to memory of 3784	1928	4aba8ea34e057b8239ff29028fa3ab829f53b2861d84a44fa9857b7d96e3a403.exe	88
PID 3784 wrote to memory of 116	3784	responder.exe	91
PID 3784 wrote to memory of 116	3784	responder.exe	91
PID 3784 wrote to memory of 116	3784	responder.exe	91
PID 3784 wrote to memory of 116	3784	responder.exe	91
PID 3784 wrote to memory of 116	3784	responder.exe	91
PID 3784 wrote to memory of 116	3784	responder.exe	91
PID 3784 wrote to memory of 116	3784	responder.exe	91
PID 3784 wrote to memory of 116	3784	responder.exe	91
PID 3784 wrote to memory of 116	3784	responder.exe	91
PID 3784 wrote to memory of 116	3784	responder.exe	91

C:\Users\Admin\AppData\Local\Temp\4aba8ea34e057b8239ff29028fa3ab829f53b2861d84a44fa9857b7d96e3a403.exe
"C:\Users\Admin\AppData\Local\Temp\4aba8ea34e057b8239ff29028fa3ab829f53b2861d84a44fa9857b7d96e3a403.exe"
1⤵
- Suspicious use of WriteProcessMemory
PID:1928
- C:\ProgramData\ErrorResponder\responder.exe
  C:\ProgramData\ErrorResponder\responder.exe "C:\Users\Admin\AppData\Local\Temp\4aba8ea34e057b8239ff29028fa3ab829f53b2861d84a44fa9857b7d96e3a403.exe" ensgJJ
  2⤵
  - Modifies WinLogon for persistence
  - Executes dropped EXE
  - Enumerates connected drives
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of WriteProcessMemory
  PID:3784
- - C:\Windows\SysWOW64\secinit.exe
    C:\ProgramData\ErrorResponder\responder.exe
    3⤵
    PID:116
  - - C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 116 -s 220
      4⤵
      Program crash
      PID:3912
- C:\Windows\SysWOW64\WerFault.exe
  C:\Windows\SysWOW64\WerFault.exe -u -p 1928 -s 444
  2⤵
  - Program crash
  PID:4832

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 444 -p 1928 -ip 1928
1⤵
PID:692

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 508 -p 116 -ip 116
1⤵
PID:4792

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

C:\ProgramData\ErrorResponder\responder.exe

Filesize
182KB

MD5
87ad62ff5669b41f8994695b3aa05cbf

SHA1
c6eb9d9a0df8ca97784b57ebe719b227ebfaf262

SHA256
4aba8ea34e057b8239ff29028fa3ab829f53b2861d84a44fa9857b7d96e3a403

SHA512
2b728b84f8377f407e293e723c5bb7813320e371d4e604323ddb397f418a367df8d925ac7d69dd53137df67f8d5b460f730f19cb94949dd14ab37da170cc47fd

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

Filesize
182KB

MD5
87ad62ff5669b41f8994695b3aa05cbf

SHA1
c6eb9d9a0df8ca97784b57ebe719b227ebfaf262

SHA256
4aba8ea34e057b8239ff29028fa3ab829f53b2861d84a44fa9857b7d96e3a403

SHA512
2b728b84f8377f407e293e723c5bb7813320e371d4e604323ddb397f418a367df8d925ac7d69dd53137df67f8d5b460f730f19cb94949dd14ab37da170cc47fd

Download Submit
memory/116-139-0x0000000000F20000-0x0000000003904000-memory.dmp

Filesize
41.9MB

Download
memory/1928-130-0x0000000000592000-0x000000000059A000-memory.dmp

Filesize
32KB

Download
memory/1928-131-0x0000000000030000-0x000000000003A000-memory.dmp

Filesize
40KB

Download
memory/1928-132-0x0000000040000000-0x00000000429E4000-memory.dmp

Filesize
41.9MB

Download
memory/3784-136-0x0000000000503000-0x000000000050B000-memory.dmp

Filesize
32KB

Download
memory/3784-137-0x0000000040000000-0x00000000429E4000-memory.dmp

Filesize
41.9MB

Download

Analysis

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