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

Static analysis result for SHA-256 8ffb4db2585e28e6…

MALICIOUS

Office (OLE) / .XLSX

329.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 88b730d9bd1dc3061c14bd67319e6957 SHA-1: 1d5ddfba9fa002e6a68693171ea6bdf28b1d2f25 SHA-256: 8ffb4db2585e28e66e2d15fa500c8efd06e8bdeda1eb70360a39a81252b9ef74
160 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File T1059.004 Scripting - Macro

The sample is an Excel file containing Excel 4.0 macros, indicated by the OLE_XLM_AUTOOPEN and OLE_XLM_DANGEROUS_FN heuristics. The presence of ShellExecute API calls and dangerous XLM functions like RUN suggests the macros are intended to execute arbitrary code. The embedded URL is likely used to download a secondary payload. The ClamAV detection name 'Doc.Downloader.Docusign0521-9864805-0' further supports its role as a downloader.

Heuristics 5

  • ClamAV: Doc.Downloader.Docusign0521-9864805-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.Docusign0521-9864805-0
  • Reference to ShellExecute API high SC_STR_SHELLEXEC
    Reference to ShellExecute API
  • XLM Auto_Open with dangerous formula APIs high 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.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://i.sfu.edu.ph/ds/161120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
e17e7cc4a238aa7ef2e84a739a77bbc946bb2881b6aa82203097e9ab8210d20f
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6273 bytes