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

Static analysis result for SHA-256 c4deed4ea94aa6cd…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 76ccbbb2404825971071c94fc4f9e6a6 SHA-1: ac74c7fc2506fb29e0435866d64f51f50c0201d4 SHA-256: c4deed4ea94aa6cdf64acd28e44d40d27871d74fc0937fc22a33fde622c08c9e
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 and ShellExecute, strongly indicates a downloader or dropper functionality. The embedded URLs, though currently flagged as unknown reputation, are likely targets for fetching the next stage of the attack. The ClamAV detection further supports the malicious classification.

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