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

Static analysis result for SHA-256 06ba15bcd24c8837…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: fd412d3c2bbca288400de0a4eb96d42c SHA-1: a9a52e6e40956271df67ec98746fca067349cfa2 SHA-256: 06ba15bcd24c8837109e0cf2dabae954da60ac417acf23655876bdd3b597cc71
242 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The file contains Excel 4.0 macros that are configured to auto-execute upon opening. These macros utilize the RUN function and a CALL function to execute code, referencing a URL (https://boatssa.com/ds/231120.gif) which likely serves as a download source for a secondary payload. The use of ShellExecute API and the presence of dangerous formula APIs in the XLM macros indicate a malicious downloader.

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://boatssa.com/ds/231120.gif
    • https://boatssa.com/ds/231120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
96eae7b570d4a9d4f225045676982008ec43ffa50f8643e2397db329f3c9bb6b
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6059 bytes