doubleback | 59de5c70ad1a5134fda141c933380bf1e55eb52e041ff37cf5394f8b9dcb5767

General

Target

document-37-1849.xls
Size

187KB
MD5

c41a21a821bcdea1d3ab26ebef055eed
SHA1

912c8c1792dd33bac263df4b71242078d74741e9
SHA256

d1d0ac76e59b9e2a8ae3a433e0186d74fc61417c89fe5ee4b93c02faa1dc58f8
SHA512

ed665e9a7d3e950318628ad4ea112da063e4f156ea7d2d58fbeaa31cc2486c7d2debb779da72723d8f55bdec6b9a4b87f9d148c50b0a368c4bc5b59ac646a42a

Score

10^/10

doubleback backdoor

Malware Config

Extracted

Language

xlm4.0

Source

URLs

xlm40.dropper

https://austinheisey.com/xls/black/index/processingSetRequestDownloadPayloader/?servername=excel

Signatures

DoubleBack
DoubleBack is a modular backdoor first seen in December 2020.
backdoor doubleback

DoubleBack x64 Payload 2 IoCs

resource	yara_rule
behavioral1/files/0x00030000000130d7-70.dat	family_doubleback_x64
behavioral1/files/0x00030000000130d7-69.dat	family_doubleback_x64

DoubleBack x86 Payload 2 IoCs

resource	yara_rule
behavioral1/files/0x00030000000130d7-70.dat	family_doubleback_x86
behavioral1/files/0x00030000000130d7-69.dat	family_doubleback_x86

Process spawned unexpected child process 1 IoCs

This typically indicates the parent process was compromised via an exploit or macro.

description	pid	pid_target	Process	procid_target
Parent C:\Program Files (x86)\Microsoft Office\Office14\EXCEL.EXE is not expected to spawn this process	1060	1832	cmd.exe	24

Downloads MZ/PE file

Executes dropped EXE 1 IoCs

pid	Process
948	pDImcT.exe

Loads dropped DLL 2 IoCs

pid	Process
1832	EXCEL.EXE
948	pDImcT.exe

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-1-5-21-2455352368-1077083310-2879168483-1000\Software\Microsoft\Internet Explorer\MenuExt\Se&nd to OneNote	EXCEL.EXE
Set value (int)	\REGISTRY\USER\S-1-5-21-2455352368-1077083310-2879168483-1000\Software\Microsoft\Internet Explorer\MenuExt\Se&nd to OneNote\Contexts = "55"	EXCEL.EXE
Key created	\REGISTRY\USER\S-1-5-21-2455352368-1077083310-2879168483-1000\Software\Microsoft\Internet Explorer\Toolbar	EXCEL.EXE
Set value (str)	\REGISTRY\USER\S-1-5-21-2455352368-1077083310-2879168483-1000\Software\Microsoft\Internet Explorer\Toolbar\ShowDiscussionButton = "Yes"	EXCEL.EXE
Key created	\REGISTRY\USER\S-1-5-21-2455352368-1077083310-2879168483-1000\Software\Microsoft\Internet Explorer\MenuExt	EXCEL.EXE
Set value (str)	\REGISTRY\USER\S-1-5-21-2455352368-1077083310-2879168483-1000\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-1-5-21-2455352368-1077083310-2879168483-1000\Software\Microsoft\Internet Explorer\MenuExt\E&xport to Microsoft Excel	EXCEL.EXE
Set value (str)	\REGISTRY\USER\S-1-5-21-2455352368-1077083310-2879168483-1000\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-1-5-21-2455352368-1077083310-2879168483-1000\Software\Microsoft\Internet Explorer\MenuExt\E&xport to Microsoft Excel\Contexts = "1"	EXCEL.EXE

Suspicious behavior: AddClipboardFormatListener 1 IoCs

pid	Process
1832	EXCEL.EXE

Suspicious use of SetWindowsHookEx 3 IoCs

pid	Process
1832	EXCEL.EXE
1832	EXCEL.EXE
1832	EXCEL.EXE

Suspicious use of WriteProcessMemory 8 IoCs

description	pid	Process	procid_target
PID 1832 wrote to memory of 1060	1832	EXCEL.EXE	31
PID 1832 wrote to memory of 1060	1832	EXCEL.EXE	31
PID 1832 wrote to memory of 1060	1832	EXCEL.EXE	31
PID 1832 wrote to memory of 1060	1832	EXCEL.EXE	31
PID 1832 wrote to memory of 948	1832	EXCEL.EXE	33
PID 1832 wrote to memory of 948	1832	EXCEL.EXE	33
PID 1832 wrote to memory of 948	1832	EXCEL.EXE	33
PID 1832 wrote to memory of 948	1832	EXCEL.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\document-37-1849.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:1832
- C:\Windows\SysWOW64\cmd.exe
  "C:\Windows\System32\cmd.exe" /c copy "%ProgramFiles(x86)%\Internet Explorer\ExtExport.exe" C:\ycjqFXSM\kO2NIybn\pDImcT.exe
  2⤵
  - Process spawned unexpected child process
  PID:1060
- C:\ycjqFXSM\kO2NIybn\pDImcT.exe
  "C:\ycjqFXSM\kO2NIybn\pDImcT.exe" C:\ycjqFXSM\kO2NIybn ALHJ zqtRI
  2⤵
  - Executes dropped EXE
  - Loads dropped DLL
  PID:948

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

1

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

Replay Monitor

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Downloads

memory/948-68-0x0000000075801000-0x0000000075803000-memory.dmp

Filesize
8KB

Download
memory/1832-60-0x000000002F7F1000-0x000000002F7F4000-memory.dmp

Filesize
12KB

Download
memory/1832-61-0x00000000713C1000-0x00000000713C3000-memory.dmp

Filesize
8KB

Download
memory/1832-62-0x000000005FFF0000-0x0000000060000000-memory.dmp

Filesize
64KB

Download

Resubmissions

Analysis

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