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

Static analysis result for SHA-256 a1fe9086bbefdf1d…

MALICIOUS

Office (OLE) / .XLSX

329.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: d94a3c9a7bde09e69f5ea971f1a7fd72 SHA-1: ecf9f290a6eb51ed25b8257d836b83ca72aa980e SHA-256: a1fe9086bbefdf1d60c26b98c9e8612619437960c67f82cd638a26e5b0b60839
160 Risk Score

Malware Insights

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

The file contains Excel 4.0 macros, indicated by the OLE_XLM_AUTOOPEN and OLE_XLM_DANGEROUS_FN heuristics. The SC_STR_SHELLEXEC firing suggests the macro attempts to execute an external command. The embedded URL and the presence of 'ShellExecute' in the document body further support the conclusion that this file is a downloader. The ClamAV detection name 'Doc.Downloader.Docusign0521-9864805-0' also points to a downloader functionality.

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 https://gaspee.info/ds/161120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
b74fbb14c9dd0283fe5b35630158622cf58bbddcd03d161d30bf64d1f40271a4
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 7889 bytes