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

Static analysis result for SHA-256 f5f7744779c0de2d…

MALICIOUS

Office (OLE) / .XLS

332.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 79bd7b39b2a820858e878f3253160a49 SHA-1: 566ce6eaa49010e3d55603da346ef936600f2cb7 SHA-256: f5f7744779c0de2d737de27ffa63aa4e52c87c2bc6ee2273065e3c86948bce83
160 Risk Score

Malware Insights

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

The file contains an Excel 4.0 macro (Auto_Open) that utilizes ShellExecute and RUN functions, indicating a downloader. The macro is likely intended to fetch and execute a payload from the embedded URL. The ClamAV detection name 'Doc.Downloader.Docusign0521-9864805-0' further supports the 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://birdexim.com/ds/231120.gif

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
33b6a73d5f0d6eaa82513d86953f6aef905a69517ef33e4eba1db75f4a178a6f
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6298 bytes