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

Static analysis result for SHA-256 9c31307d7a3cf7dc…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 0ede112b092ef01f49e8e1df324989d6 SHA-1: 35025eb08412014b0757ed2757d3e6a8ad25cadb SHA-256: 9c31307d7a3cf7dce4494db9a08fe48f6fda55db12d968af0d708fc818a9d637
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 presence of Excel 4.0 macros, specifically an Auto_Open function utilizing dangerous APIs like RUN, strongly indicates malicious intent. The macro is designed to execute a secondary payload by downloading it from the provided URL. The ClamAV detection name 'Doc.Downloader' further supports this, suggesting the primary function is to download and execute further malware. The confidence is slightly reduced due to the lack of direct script content 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://ctxpress.com/ds/261120.gif
    • https://ctxpress.com/ds/261120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
aa837a287543a9593dc9ad53c5a1043539349d9d7158b9d02f92e2bb7330dc0f
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6677 bytes