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

Static analysis result for SHA-256 49600d50a08ef27d…

MALICIOUS

Office (OLE) / .XLS

133.0 KB Created: 2019-02-16 06:17:00 Authoring application: Microsoft Excel
MD5: 98b528bb6369cceaaa92cc22bbea9ccd SHA-1: f9dcfe474c1ea8cefd6c55f4eccfc7496a44a57f SHA-256: 49600d50a08ef27d291445a53aae70ec3097484229aa9f6d12e4cbd181082a15
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1059.001 PowerShell

The file is an Excel 4.0 (XLM) macro-enabled spreadsheet. Heuristics indicate the presence of an Auto_Open macro that uses dangerous functions, including the RUN function. The document body contains text that prompts the user to 'Enable Editing and Enable Content', a common lure for macro-based attacks. No specific malware family was identified, but the macro execution is designed to bypass security warnings and likely download or execute a secondary payload.

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
186afe9b50b7e848829a6a59ad9d51f9c7d2b0862bc3471b61b9ad89e43ed008
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 80036 bytes