buer | 711a05c2b42db93458407fc8d81cdd8d5c92a5cf44e5cab4e9ca58f5267d3cab

General

Target

Notice-Delivery2020.xlsm
Size

430KB
MD5

0b49c3bd2479bed644ee5f0a21bdeabb
SHA1

2f63381e01e5c6c2dd0b2759a645c7aae6019a49
SHA256

711a05c2b42db93458407fc8d81cdd8d5c92a5cf44e5cab4e9ca58f5267d3cab
SHA512

9d3b2e7d253b18a3cdcd05f908c8826e33401bb34ece07d42f0ee0f53b5f9d1a66f85459990bdf43401a8970e9d4cbe5c482f2578fcbec9994dbebaacb95a459

Score

10^/10

buer loader

Malware Config

Extracted

Family

buer

C2

heartprogseds.com

Signatures

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

Buer Loader 3 IoCs

Detects Buer loader in memory or disk.

resource	yara_rule
behavioral1/memory/1340-8-0x0000000040000000-0x0000000040009000-memory.dmp	buer
behavioral1/memory/524-11-0x00000000007A0000-0x00000000007A9000-memory.dmp	buer
behavioral1/memory/1340-9-0x0000000040005DA8-mapping.dmp	buer

Executes dropped EXE 2 IoCs

pid	Process
524	MSettingExcel.exe
1340	MSettingExcel.exe

Loads dropped DLL 2 IoCs

pid	Process
1640	EXCEL.EXE
524	MSettingExcel.exe

Suspicious use of SetThreadContext 1 IoCs

description	pid	Process	procid_target
PID 524 set thread context of 1340	524	MSettingExcel.exe	33

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/0x0003000000013131-3.dat	nsis_installer_1
behavioral1/files/0x0003000000013131-3.dat	nsis_installer_2
behavioral1/files/0x0003000000013131-5.dat	nsis_installer_1
behavioral1/files/0x0003000000013131-5.dat	nsis_installer_2
behavioral1/files/0x0003000000013131-6.dat	nsis_installer_1
behavioral1/files/0x0003000000013131-6.dat	nsis_installer_2
behavioral1/files/0x0003000000013131-10.dat	nsis_installer_1
behavioral1/files/0x0003000000013131-10.dat	nsis_installer_2

Enumerates system info in registry 2 TTPs 1 IoCs

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key opened	\REGISTRY\MACHINE\Hardware\Description\System\FloatingPointProcessor	EXCEL.EXE

Modifies Internet Explorer settings 1 TTPs 9 IoCs

adware spyware

Modify Registry

T1112

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-3825035466-2522850611-591511364-1000\Software\Microsoft\Internet Explorer\MenuExt	EXCEL.EXE
Key created	\REGISTRY\USER\S-1-5-21-3825035466-2522850611-591511364-1000\Software\Microsoft\Internet Explorer\MenuExt\Se&nd to OneNote	EXCEL.EXE
Set value (str)	\REGISTRY\USER\S-1-5-21-3825035466-2522850611-591511364-1000\Software\Microsoft\Internet Explorer\MenuExt\Se&nd to OneNote\ = "res://C:\\PROGRA~2\\MICROS~1\\Office14\\ONBttnIE.dll/105"	EXCEL.EXE
Key created	\REGISTRY\USER\S-1-5-21-3825035466-2522850611-591511364-1000\Software\Microsoft\Internet Explorer\MenuExt\E&xport to Microsoft Excel	EXCEL.EXE
Key created	\REGISTRY\USER\S-1-5-21-3825035466-2522850611-591511364-1000\Software\Microsoft\Internet Explorer\Toolbar	EXCEL.EXE
Set value (str)	\REGISTRY\USER\S-1-5-21-3825035466-2522850611-591511364-1000\Software\Microsoft\Internet Explorer\Toolbar\ShowDiscussionButton = "Yes"	EXCEL.EXE
Set value (int)	\REGISTRY\USER\S-1-5-21-3825035466-2522850611-591511364-1000\Software\Microsoft\Internet Explorer\MenuExt\Se&nd to OneNote\Contexts = "55"	EXCEL.EXE
Set value (str)	\REGISTRY\USER\S-1-5-21-3825035466-2522850611-591511364-1000\Software\Microsoft\Internet Explorer\MenuExt\E&xport to Microsoft Excel\ = "res://C:\\PROGRA~2\\MICROS~1\\Office14\\EXCEL.EXE/3000"	EXCEL.EXE
Set value (int)	\REGISTRY\USER\S-1-5-21-3825035466-2522850611-591511364-1000\Software\Microsoft\Internet Explorer\MenuExt\E&xport to Microsoft Excel\Contexts = "1"	EXCEL.EXE

Suspicious behavior: AddClipboardFormatListener 1 IoCs

pid	Process
1640	EXCEL.EXE

Suspicious behavior: MapViewOfSection 1 IoCs

pid	Process
524	MSettingExcel.exe

Suspicious use of SetWindowsHookEx 3 IoCs

pid	Process
1640	EXCEL.EXE
1640	EXCEL.EXE
1640	EXCEL.EXE

Suspicious use of WriteProcessMemory 9 IoCs

description	pid	Process	procid_target
PID 1640 wrote to memory of 524	1640	EXCEL.EXE	31
PID 1640 wrote to memory of 524	1640	EXCEL.EXE	31
PID 1640 wrote to memory of 524	1640	EXCEL.EXE	31
PID 1640 wrote to memory of 524	1640	EXCEL.EXE	31
PID 524 wrote to memory of 1340	524	MSettingExcel.exe	33
PID 524 wrote to memory of 1340	524	MSettingExcel.exe	33
PID 524 wrote to memory of 1340	524	MSettingExcel.exe	33
PID 524 wrote to memory of 1340	524	MSettingExcel.exe	33
PID 524 wrote to memory of 1340	524	MSettingExcel.exe	33

C:\Program Files (x86)\Microsoft Office\Office14\EXCEL.EXE
"C:\Program Files (x86)\Microsoft Office\Office14\EXCEL.EXE" /dde C:\Users\Admin\AppData\Local\Temp\Notice-Delivery2020.xlsm
1⤵
- Loads dropped DLL
- Enumerates system info in registry
- Modifies Internet Explorer settings
- Suspicious behavior: AddClipboardFormatListener
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
PID:1640
- C:\offic\offiekra\MSettingExcel.exe
  "C:\offic\offiekra\MSettingExcel.exe"
  2⤵
  - Executes dropped EXE
  - Loads dropped DLL
  - Suspicious use of SetThreadContext
  - Suspicious behavior: MapViewOfSection
  - Suspicious use of WriteProcessMemory
  PID:524
- - C:\offic\offiekra\MSettingExcel.exe
    "C:\offic\offiekra\MSettingExcel.exe"
    3⤵
    - Executes dropped EXE
    PID:1340

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Privilege Escalation

Defense Evasion

Modify Registry

1

T1112

Credential Access

Discovery

Query Registry

1

T1012

System Information Discovery

2

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

Replay Monitor

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Downloads

memory/524-11-0x00000000007A0000-0x00000000007A9000-memory.dmp

Filesize
36KB

Download
memory/1340-8-0x0000000040000000-0x0000000040009000-memory.dmp

Filesize
36KB

Download
memory/1700-2-0x000007FEF7B10000-0x000007FEF7D8A000-memory.dmp

Filesize
2.5MB

Download

Analysis

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