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

Static analysis result for SHA-256 4a841eaf90cd8d71…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: e3db5f3724c6ff981d447073b3c754f6 SHA-1: 06781b3ae07a46c802511b9e8af134e392a954ec SHA-256: 4a841eaf90cd8d71a6dfd4024043eb2d77ae58cfc78c9b1a6453a43acc82a1b1
160 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File T1059.001 PowerShell T1105 Ingress Tool Transfer

The sample is an Excel file containing Excel 4.0 macros, indicated by the OLE_XLM_AUTOOPEN and OLE_XLM_DANGEROUS_FN heuristics. The macros utilize ShellExecute to download a payload from the embedded URL http://l.loungu.com/ds/231120.gif. The ClamAV detection name 'Doc.Downloader.Docusign0521-9864805-0' further suggests a 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 http://l.loungu.com/ds/231120.gif
    • http://l.loungu.com/ds/231120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
abb07963271b08693dfd8d409076720f3110aa546c958d7d37a9d0626b110da2
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6297 bytes