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

Static analysis result for SHA-256 75358e460d7f0c61…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 90fce2644210a1001f1ba8740a5ad649 SHA-1: abb109f2e2ec243cb7c96f2eb916b69b84e77d1c SHA-256: 75358e460d7f0c614937cfc7b532736c99ad09fd8bee3c1fb86859ef0715b28f
242 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution

The file contains Excel 4.0 macros with an Auto_Open entry, which is a critical finding. These macros utilize dangerous functions like RUN and CALL, and specifically reference ShellExecute, indicating an attempt to execute arbitrary code. The macros also construct strings that appear to form URLs, such as "UR"& DocuSig!BY111&"n", suggesting a downloader functionality that contacts the domain binbios.com.

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://binbios.com/ds/261120.gif
    • https://binbios.com/ds/261120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
db00faaaa5dfbd9a76904fe95aa20bad9a05f6214a6081cc43218c3c9509e31c
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6676 bytes