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

Static analysis result for SHA-256 ddc8878c4b38a9da…

MALICIOUS

Office (OLE) / .XLSX

329.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: bdfe1c671988a192c4c7810b9698541d SHA-1: db2bc22e052822cdd03a6922190cb7d497b4e296 SHA-256: ddc8878c4b38a9da71f9c198cbc0ef4aaccae87898b0b930c55d1ec3bb141f9e
160 Risk Score

Malware Insights

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

The presence of Excel 4.0 macros, specifically the Auto_Open function utilizing dangerous APIs like RUN, strongly indicates malicious intent. The heuristic firing for ShellExecute further suggests the execution of external commands. The embedded URL is likely used to download and execute a secondary payload, as indicated by the ClamAV detection name 'Doc.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://ippp.co.zw/ds/161120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
de64c8aedb9841e9622ce89b4c2a59532a2613bac9a0b05117fd5443ba276b2f
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 7888 bytes