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

Static analysis result for SHA-256 aa6cda38c5d22259…

MALICIOUS

Office (OLE) / .XLSX

329.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 3fdf9728c0e2d2893b67190d9f2be16a SHA-1: bb2c1d411d9e8dbd83ad18ff62b83ff140d3e891 SHA-256: aa6cda38c5d22259cb63555de3660ed4fdbe64ccc4adfcd98d2d356db3d02754
160 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File T1059.001 PowerShell

The presence of Excel 4.0 macros, specifically an Auto_Open macro utilizing dangerous functions like RUN and ShellExecute, strongly indicates malicious intent. The embedded URL likely serves as a distribution point for a second-stage payload. The ClamAV detection further supports the classification 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://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