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

Static analysis result for SHA-256 6515c47c1fe18dc7…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: f0c545ca81d7742f6409e80ac1522ea2 SHA-1: abde80780d43d2dde98973e76248bfbd3146c4bd SHA-256: 6515c47c1fe18dc7c9f92bf95df962931a2ea49f1cf4410c8c21aff6a54bc84a
242 Risk Score

Malware Insights

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

The file contains Excel 4.0 macros with an Auto_Open entry, which is a critical finding indicating automatic execution upon opening. The macros utilize the RUN function and a CALL to ShellExecute-like functionality, specifically referencing 'Ke32' and 'CryA', suggesting the execution of a downloaded payload. The embedded URL 'https://boatssa.com/ds/231120.gif' is highly suspicious and likely serves as the source for this payload. The ClamAV detection further confirms its malicious nature as a 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