Office (OOXML) malware analysis — malicious · a806686b567ee3c9

MALICIOUS

Office (OOXML)

42.0 KB Created: 2021-06-22 12:43:05 UTC Authoring application: Microsoft Excel 16.0300

MD5: f71e8dfcb74e6e41a97bd6e9c60b5e67 SHA-1: 6d78c0a0be761b764fb3c00eda747310e71bf5fc SHA-256: a806686b567ee3c95a5f3467209e88b9ba62bf10f9783004873c802ac4f4cd1d

260 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic T1059.001 PowerShell T1218.011 System Binary Proxy Execution: Rundll32

The file is an Office document containing VBA macros. The Workbook_Open macro is present and references cmd.exe and PowerShell, indicating an attempt to execute external commands. The critical heuristic 'VBA WMI Win32_Process launcher' suggests the macro uses WMI to launch processes, likely to download and execute a second-stage payload. The presence of a Base64 decoding function within the VBA code further supports the idea of obfuscated malicious code execution.

Heuristics 6

PowerShell reference in VBA critical OLE_VBA_PS

PowerShell reference in VBA
VBA WMI Win32_Process launcher critical OLE_VBA_WMI_PROCESS_CREATE

VBA macro builds or references a WMI moniker for Win32_Process and invokes .Create to start a command. This is a high-confidence macro execution chain that often hides the WMI class name through string concatenation or helper functions.
Workbook_Open macro high OLE_VBA_WBOPEN

Workbook_Open macro
GetObject call high OLE_VBA_GETOBJ

GetObject call
cmd.exe reference in VBA high OLE_VBA_CMD

cmd.exe reference in VBA
VBA project inside OOXML medium OOXML_VBA

Document contains a VBA project — VBA macros present

Extracted artifacts 2

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`macros.bas` `6444cb2b0076bc5f2b4bccc62495ac00cd7221cf0407ffcfac93752a20c6003c`	vba-macro	oletools.olevba.extract_macros (decoded VBA source from OOXML)	35707 bytes
`vbaProject_00.bin` `f056b8d257374989b21b04082943cf6c0b1ecc8e45367ac1db61fe63d131598f`	vba-project	OOXML VBA project: xl/vbaProject.bin	11776 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.