Office (OOXML) / .XLSX malware analysis — malicious · bd96b4b598395306

MALICIOUS

Office (OOXML) / .XLSX

165.8 KB Created: 2021-03-22 13:12:00 UTC Authoring application: Microsoft Excel 15.0300 First seen: 2022-07-13

MD5: 810db3a9e5c7e3166856dc87b793e2d3 SHA-1: 77609542755928e33ad15c884f04e29aeb3622dc SHA-256: bd96b4b5983953068c1ccc84907cc9f666e1ba959ac053d64cba7609c1fce492

200 Risk Score

Malware Insights

MITRE ATT&CK

T1059.001 PowerShell T1218 Signed Binary Proxy Execution T1059 Command and Scripting Interpreter

The sample is an Excel spreadsheet containing a Workbook_Open macro, which is a common technique for automatic execution. The critical heuristic indicates the macro uses GetObject to launch a Win32_Process via WMI, likely to execute a secondary payload. No specific family could be identified, but the execution method is clear.

Heuristics 5

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
VBA p-code auto-exec with execution tokens high OLE_VBA_PCODE_AUTOEXEC_EXEC

Compiled VBA/cache stream contains an auto-execution token together with shell/download/object-execution tokens. This catches p-code-only or source-extraction-failure macro documents where visible source is unavailable.
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` `08b4bdd5554814474e2dff2a500b6873900f1ac8b273a6f20902a1affec976b3`	vba-macro	oletools.olevba.extract_macros (decoded VBA source from OOXML)	7689 bytes
`vbaProject_00.bin` `510d9c472a70c85c4bb433210a03f88b0c69a4222ec2f2b948ba72959b7484f5`	vba-project	OOXML VBA project: xl/vbaProject.bin	59392 bytes

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