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

Static analysis result for SHA-256 c536a7b15098603b…

MALICIOUS

Office (OLE) / .XLSX

332.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: c6d0d7d03186d1312a8d0b88c241080b SHA-1: 0e4e6066d73809dc8a2d667b1f43f1c4aa2c2e35 SHA-256: c536a7b15098603b6ac00617ca3aba6882c8e556fea6e6a4fe972cd13b64c6a9
160 Risk Score

Malware Insights

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

The sample contains Excel 4.0 macros, indicated by the OLE_XLM_AUTOOPEN and OLE_XLM_DANGEROUS_FN heuristics. The SC_STR_SHELLEXEC heuristic confirms the use of the ShellExecute API, which is often used to launch downloaded payloads. The embedded URL is likely the source for this 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://cloud.c-tes.gr/ds/151120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
89aad7b8576d8f84c1934acd2fc0826a9bcea7c600ce1ac7e8579bafe1fef843
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 5602 bytes