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

Static analysis result for SHA-256 8ae916c2b6bb3970…

MALICIOUS

Office (OLE) / .XLSX

332.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 231eb86f18d86bb28ba0581957d6bc8d SHA-1: d56cc1e201bfc1844c3d9709f78a7dee345a2f90 SHA-256: 8ae916c2b6bb3970c4c26b8c4279d64881e2d64092c17d22027e622cd34102d8
160 Risk Score

Malware Insights

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

The sample contains Excel 4.0 (XLM) macros, indicated by the OLE_XLM_AUTOOPEN and OLE_XLM_DANGEROUS_FN heuristics. The SC_STR_SHELLEXEC firing suggests the macro attempts to execute a command or file. The embedded URL http://cloud.c-tes.gr/ds/151120.gif is likely used to download and execute a second-stage payload. The ClamAV detection further confirms its malicious nature.

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