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

Static analysis result for SHA-256 08c473aeb67e2af8…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: cb16cfaacce95ddbd3a8dc1c52ce8f1e SHA-1: 51067e61837fa422963e0a0ca3ae5078f53fec28 SHA-256: 08c473aeb67e2af8d019e5060d595a7d5acd04ee55efb959382e4dcb6601189f
242 Risk Score

Malware Insights

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

This Excel 4.0 macro-enabled workbook contains an Auto_Open macro that executes a CALL function. This function appears to be constructing a command to download a payload from the URL https://chica.media/ds/231120.gif. The use of XLM macros and the ShellExecute API reference indicate a downloader functionality.

Heuristics 6

  • Excel 4.0 Auto_Open defined name critical OLE_XLM_AUTOOPEN_DEFINEDNAME
    oletools recovered an Auto_Open / Auto_Close entry from an Excel 4.0 macro sheet. The raw BIFF name can be tokenized or partially opaque to byte-string checks, but the recovered macro listing confirms the workbook has an XLM auto-execution entry.
  • XLM Auto_Open with dangerous formula APIs critical 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.
  • 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
  • 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://chica.media/ds/231120.gif
    • https://chica.media/ds/231120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
f47affe8c13bcf147c60cdfcb7548aa5c789e981f4872a53ebdda3b841e12f12
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6059 bytes