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

Static analysis result for SHA-256 31f32aa38a987ca6…

MALICIOUS

Office (OLE) / .XLSX

58.5 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel
MD5: 701b816309429adca3a7c278b89b7dcc SHA-1: 0c2b5849949b4708ede63ba8f560eb6632ffbfda SHA-256: 31f32aa38a987ca660553f3ed615c44f096e23ff80192a7922f273b1e474858b
160 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File

The sample is an Excel 4.0 macro-enabled spreadsheet that uses an Auto_Open macro to execute. The presence of the 'SE_ENABLE_LURE' heuristic indicates a user-facing prompt to enable macros. The XLM macro contains calls to dangerous functions like RUN, suggesting it attempts to download and execute a second-stage payload from the URL http://www.psicheaurora.it/fanta/download.php. The macro also references 'ndll32' and ',DllRegisterServer', indicating potential dynamic-link library registration or execution.

Heuristics 4

  • 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.
  • XLM Auto_Open with dangerous formula APIs critical OLE_XLM_DANGEROUS_FN
    Excel 4.0 macro sheet contains an Auto_Open / Auto_Close entry and dangerous XLM formula APIs that can invoke programs, write files, or transfer control without VBA.
  • 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
f4049687de69fbae7a0009d349264e905f03c629c5b7f7eb1990c6538d126bea
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 2738 bytes