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

Static analysis result for SHA-256 d33ac9116831e4b3…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 9f87f7204046b27c4a14be9afff7b36e SHA-1: fdb4ff6bf2e25ed256bcd9ddeb0f1961d1e6e7e4 SHA-256: d33ac9116831e4b3cb93fc902e4b5340761f0226cc3493cbb017157b4a249e42
160 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File T1059.004 Shell Script

The sample contains Excel 4.0 macros, specifically an Auto_Open macro that utilizes dangerous functions like RUN and ShellExecute. This indicates the macro is intended to execute arbitrary code. The embedded URL likely serves as a distribution point for a second-stage payload, as suggested 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 https://seligue.net/ds/231120.gif
    • https://seligue.net/ds/231120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
7d52b160b251e749d24dcaa8a7221d3fa1a2d506bf23ecf06e056242a80d0dfe
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6297 bytes