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

Static analysis result for SHA-256 36de03cc2680919b…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 316de397e310db299ffbc26c91965c6d SHA-1: ebb9195a06f2256c2c72b2e8fe9ae52965c7c74d SHA-256: 36de03cc2680919b3b99fec313055f1e1510759eb4bcd15254e5d58db0385217
160 Risk Score

Malware Insights

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

The presence of Excel 4.0 macros, specifically an Auto_Open function utilizing dangerous APIs like RUN, strongly indicates malicious intent. The ShellExecute API reference further suggests the execution of external commands, likely to download and run a secondary payload from the embedded URLs. The ClamAV detection as Doc.Downloader.Docusign0521-9864805-0 supports this analysis.

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://ump.edu.pe/ds/261120.gif
    • https://ump.edu.pe/ds/261120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
56d07016068e454a1af96b6cee33e5364bc7ae97582ff73833a2c41ba0035917
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6675 bytes