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

Static analysis result for SHA-256 b3ce3700702234e3…

MALICIOUS

Office (OLE) / .XLS

41.0 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel
MD5: 7ea267b39bd99b1c0b5e215d539eb50a SHA-1: 78d203afd8a1fb515c37820e769ea3adddcd0120 SHA-256: b3ce3700702234e38e52e77ae2f0082f6855f0e6afc5a8dea92a1002ffba51f7
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1059.001 PowerShell T1059.003 Windows Command Shell

The file contains Excel 4.0 macros, specifically an Auto_Open function, which is a known technique for executing malicious code. The critical heuristic firings indicate the presence of dangerous formula APIs like 'RUN=0', suggesting the macro is designed to execute arbitrary commands. No specific URLs or hashes were extracted, but the presence of the Auto_Open macro is a strong indicator of malicious intent.

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
ba9d41b4368b16166ae8fefc50011e8b9669696dd0cfd0c6866171baf32c18a5
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8056 bytes