buer | 7c70ee2493d0ccc41cf42d9ef1f478d235bb09fa98eb1e991d7f4bccac818bf0

General

Target

2.exe
Size

36KB
MD5

4d85e1d2cff1f97e149e345a19928ad9
SHA1

2c1c6df0d80940bed3576ba89bd8b0f29654bb17
SHA256

7c70ee2493d0ccc41cf42d9ef1f478d235bb09fa98eb1e991d7f4bccac818bf0
SHA512

d0afa20c1cf1fbdb197dc846e862478fa156b1331b4b4cf1e96520c7981c87de2c25c0dbdebcf6749212c56f70443b3792a133e1261210cf1298358535221f1f

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 2 IoCs

persistence

Winlogon Helper DLL

T1004

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\USER\S-1-5-21-790714498-1549421491-1643397139-1000\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\ProgramData\\ErrorResponder\\responder.exe\""	responder.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-790714498-1549421491-1643397139-1000\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\ProgramData\\ErrorResponder\\responder.exe\""	secinit.exe

Buer Loader 3 IoCs

Detects Buer loader in memory or disk.

resource	yara_rule
behavioral2/files/0x000a00000001e7b1-130.dat	buer
behavioral2/files/0x000a00000001e7b1-131.dat	buer
behavioral2/memory/2252-133-0x0000000002C40000-0x0000000002C4C000-memory.dmp	buer

Executes dropped EXE 1 IoCs

pid	Process
4024	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)	\??\P:	secinit.exe
File opened (read-only)	\??\Q:	secinit.exe
File opened (read-only)	\??\X:	secinit.exe
File opened (read-only)	\??\I:	secinit.exe
File opened (read-only)	\??\J:	secinit.exe
File opened (read-only)	\??\K:	secinit.exe
File opened (read-only)	\??\R:	secinit.exe
File opened (read-only)	\??\S:	secinit.exe
File opened (read-only)	\??\T:	secinit.exe
File opened (read-only)	\??\Z:	secinit.exe
File opened (read-only)	\??\G:	secinit.exe
File opened (read-only)	\??\L:	secinit.exe
File opened (read-only)	\??\O:	secinit.exe
File opened (read-only)	\??\N:	secinit.exe
File opened (read-only)	\??\V:	secinit.exe
File opened (read-only)	\??\W:	secinit.exe
File opened (read-only)	\??\E:	secinit.exe
File opened (read-only)	\??\F:	secinit.exe
File opened (read-only)	\??\M:	secinit.exe
File opened (read-only)	\??\U:	secinit.exe
File opened (read-only)	\??\Y:	secinit.exe
File opened (read-only)	\??\A:	secinit.exe
File opened (read-only)	\??\B:	secinit.exe
File opened (read-only)	\??\H:	secinit.exe

Suspicious behavior: EnumeratesProcesses 2 IoCs

pid	Process
2252	secinit.exe
2252	secinit.exe

Suspicious use of WriteProcessMemory 13 IoCs

description	pid	Process	procid_target
PID 1800 wrote to memory of 4024	1800	2.exe	72
PID 1800 wrote to memory of 4024	1800	2.exe	72
PID 1800 wrote to memory of 4024	1800	2.exe	72
PID 4024 wrote to memory of 2252	4024	responder.exe	73
PID 4024 wrote to memory of 2252	4024	responder.exe	73
PID 4024 wrote to memory of 2252	4024	responder.exe	73
PID 4024 wrote to memory of 2252	4024	responder.exe	73
PID 4024 wrote to memory of 2252	4024	responder.exe	73
PID 4024 wrote to memory of 2252	4024	responder.exe	73
PID 4024 wrote to memory of 2252	4024	responder.exe	73
PID 4024 wrote to memory of 2252	4024	responder.exe	73
PID 4024 wrote to memory of 2252	4024	responder.exe	73
PID 4024 wrote to memory of 2252	4024	responder.exe	73

C:\Users\Admin\AppData\Local\Temp\2.exe
"C:\Users\Admin\AppData\Local\Temp\2.exe"
1⤵
- Suspicious use of WriteProcessMemory
PID:1800
- C:\ProgramData\ErrorResponder\responder.exe
  C:\ProgramData\ErrorResponder\responder.exe "C:\Users\Admin\AppData\Local\Temp\2.exe" ensgJJ
  2⤵
  - Modifies WinLogon for persistence
  - Executes dropped EXE
  - Suspicious use of WriteProcessMemory
  PID:4024
- - C:\Windows\SysWOW64\secinit.exe
    C:\ProgramData\ErrorResponder\responder.exe
    3⤵
    - Modifies WinLogon for persistence
    - Enumerates connected drives
    - Suspicious behavior: EnumeratesProcesses
    PID:2252

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/2252-132-0x0000000002C50000-0x0000000002C51000-memory.dmp

Filesize
4KB

Download
memory/2252-133-0x0000000002C40000-0x0000000002C4C000-memory.dmp

Filesize
48KB

Download

Analysis

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