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

Static analysis result for SHA-256 87f604f8cd00178f…

MALICIOUS

Office (OLE) / .XLS

332.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: fa2978f8b28e47ec97cbf408a8a9c691 SHA-1: 59bc51935e06e33625b38a5c783f3d6bdae62ec5 SHA-256: 87f604f8cd00178fc4e7147ee6fed997b1456b01f1146ad8383a8dd864fe4bba
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 contains Excel 4.0 macros, specifically an Auto_Open function that utilizes dangerous APIs like RUN. This indicates an attempt to execute arbitrary code. The presence of an embedded URL suggests the macro is designed to download and execute a second-stage payload, likely leading to further infection. The ClamAV detection name 'Doc.Downloader.Docusign0521-9864805-0' further supports this 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 https://birdexim.com/ds/231120.gif

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
33b6a73d5f0d6eaa82513d86953f6aef905a69517ef33e4eba1db75f4a178a6f
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6298 bytes