buer | dd6a316b8476993c98d452e05bae3441426cd074a165dab259183cfb64a7b23c

General

Target

Invoice106237.xls
Size

254KB
MD5

d99588c5238094b5c43ade66067fac80
SHA1

9fba7c1073ab55f4f4373f9df4af60602b487560
SHA256

dd6a316b8476993c98d452e05bae3441426cd074a165dab259183cfb64a7b23c
SHA512

e23f46341bd206219522fbb18154d3d48b5835281b107d2dba215e985e08b210307ff3dd54a39724045ec5a7427a76c4985e920e68f7c12feff53673adea8a24

Score

10^/10

buer loader

Malware Config

Extracted

Language

xlm4.0

Source

URLs

xlm40.dropper

https://goldforexinstitute.com/wp-admin/images/gif/faxer.txt

Extracted

Family

buer

C2

tokacpebanking.com

Signatures

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

Buer Loader 1 IoCs

Detects Buer loader in memory or disk.

resource	yara_rule
behavioral1/memory/548-14-0x0000000040000000-0x000000004000A000-memory.dmp	buer

Executes dropped EXE 2 IoCs

pid	Process
436	windowsphoto.exe
548	windowsphoto.exe

Loads dropped DLL 2 IoCs

pid	Process
912	EXCEL.EXE
436	windowsphoto.exe

Suspicious use of SetThreadContext 1 IoCs

description	pid	Process	procid_target
PID 436 set thread context of 548	436	windowsphoto.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 10 IoCs

installer

resource	yara_rule
	nsis_installer_1
	nsis_installer_2
behavioral1/files/0x00040000000130f2-6.dat	nsis_installer_1
behavioral1/files/0x00040000000130f2-6.dat	nsis_installer_2
behavioral1/files/0x00040000000130f2-8.dat	nsis_installer_1
behavioral1/files/0x00040000000130f2-8.dat	nsis_installer_2
behavioral1/files/0x00040000000130f2-10.dat	nsis_installer_1
behavioral1/files/0x00040000000130f2-10.dat	nsis_installer_2
behavioral1/files/0x00040000000130f2-13.dat	nsis_installer_1
behavioral1/files/0x00040000000130f2-13.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
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
Set value (str)	\REGISTRY\USER\S-1-5-21-3825035466-2522850611-591511364-1000\Software\Microsoft\Internet Explorer\Toolbar\ShowDiscussionButton = "Yes"	EXCEL.EXE
Key created	\REGISTRY\USER\S-1-5-21-3825035466-2522850611-591511364-1000\Software\Microsoft\Internet Explorer\MenuExt	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\Se&nd to OneNote\Contexts = "55"	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
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

Suspicious behavior: AddClipboardFormatListener 1 IoCs

pid	Process
912	EXCEL.EXE

Suspicious behavior: MapViewOfSection 1 IoCs

pid	Process
436	windowsphoto.exe

Suspicious use of SetWindowsHookEx 6 IoCs

pid	Process
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE

Suspicious use of WriteProcessMemory 9 IoCs

description	pid	Process	procid_target
PID 912 wrote to memory of 436	912	EXCEL.EXE	31
PID 912 wrote to memory of 436	912	EXCEL.EXE	31
PID 912 wrote to memory of 436	912	EXCEL.EXE	31
PID 912 wrote to memory of 436	912	EXCEL.EXE	31
PID 436 wrote to memory of 548	436	windowsphoto.exe	33
PID 436 wrote to memory of 548	436	windowsphoto.exe	33
PID 436 wrote to memory of 548	436	windowsphoto.exe	33
PID 436 wrote to memory of 548	436	windowsphoto.exe	33
PID 436 wrote to memory of 548	436	windowsphoto.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\Invoice106237.xls
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:912
- C:\BlockSt\Uptqeodk\windowsphoto.exe
  "C:\BlockSt\Uptqeodk\windowsphoto.exe"
  2⤵
  - Executes dropped EXE
  - Loads dropped DLL
  - Suspicious use of SetThreadContext
  - Suspicious behavior: MapViewOfSection
  - Suspicious use of WriteProcessMemory
  PID:436
- - C:\BlockSt\Uptqeodk\windowsphoto.exe
    "C:\BlockSt\Uptqeodk\windowsphoto.exe"
    3⤵
    - Executes dropped EXE
    PID:548

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

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Downloads

memory/436-9-0x0000000076381000-0x0000000076383000-memory.dmp

Filesize
8KB

Download
memory/548-14-0x0000000040000000-0x000000004000A000-memory.dmp

Filesize
40KB

Download
memory/912-4-0x000000005FFF0000-0x0000000060000000-memory.dmp

Filesize
64KB

Download
memory/912-2-0x000000002FA61000-0x000000002FA64000-memory.dmp

Filesize
12KB

Download
memory/912-3-0x0000000071771000-0x0000000071773000-memory.dmp

Filesize
8KB

Download
memory/912-15-0x000000005FFF0000-0x0000000060000000-memory.dmp

Filesize
64KB

Download
memory/912-16-0x0000000002060000-0x0000000002061000-memory.dmp

Filesize
4KB

Download
memory/1112-5-0x000007FEF6580000-0x000007FEF67FA000-memory.dmp

Filesize
2.5MB

Download

Analysis

Sharing

General

Malware Config

Extracted

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v6

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Downloads