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

Static analysis result for SHA-256 c6ad14b63256a94b…

MALICIOUS

Office (OLE) / .XLS

34.0 KB Created: 2020-12-02 13:27:18 Authoring application: Microsoft Excel
MD5: 3352434005a0c86e229df681369fc997 SHA-1: d16be03346fb1a2ec7ba88da472c14aa0aa0dfae SHA-256: c6ad14b63256a94be640ce2b8f4378ca8c329c5350ebd8ecfd7651695fe517dc
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1566.002 Spearphishing Attachment

The file is an Excel 4.0 (XLM) macro-enabled spreadsheet. Heuristics indicate the presence of an Auto_Open macro that uses dangerous functions, specifically the RUN function. The document body contains a social engineering lure, instructing the user to 'Enable Editing' and 'Enable Content' to view or edit the document, which is a common tactic for macro-based malware delivery. The XLM macro sheet contains references to sheet names and cell locations, but no direct URLs or executable commands were recovered.

Heuristics 3

  • 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.
  • 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.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
38871d4346115a71429487ac4b0f4f1c78d0d9c6fcce14428c8039dd4b1b12fd
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 3444 bytes