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

Static analysis result for SHA-256 6b300bdfd58a0764…

MALICIOUS

Office (OLE) / .XLS

331.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: cce65f5f3e059c8c8b367fb7cbde1432 SHA-1: c95d0bc173d9d7c9ee9998b2fac7c9f93b121c41 SHA-256: 6b300bdfd58a0764a32f62e7bba345c2726cba20574b47fde310b93234cc3cfd
242 Risk Score

Malware Insights

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

This Excel 4.0 macro-enabled workbook contains an Auto_Open macro that utilizes the RUN function to execute a formula. This formula, in turn, calls the 'CreateA' function from 'kernel32' with a concatenated string, likely to download and execute a payload from the embedded URL. The presence of the 'CALL' function and the embedded URL strongly suggests a downloader or droppper 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