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

Static analysis result for SHA-256 49ab77fa70e4b183…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 8338758aa016374ef1e24b6006a7b755 SHA-1: 86235bb6b84a4a0212830792a2bb526738464d1f SHA-256: 49ab77fa70e4b183acfd4247f75d18bc2a43ad87e480e8a00f745a6fe9d69265
160 Risk Score

Malware Insights

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

The sample contains Excel 4.0 macros, specifically an Auto_Open macro that utilizes dangerous functions like RUN. This macro likely executes a downloader payload, as indicated by the ShellExecute API reference and the embedded URL pointing to a GIF file, which is a common technique for obfuscating malicious content. The ClamAV detection name further supports this assessment.

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://oyefauji.com/ds/261120.gif
    • https://oyefauji.com/ds/261120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
58a4f5727165121d868a3a8deb557c7e948c3b637eb6aacf726ea069bd257a4e
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6677 bytes