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

Static analysis result for SHA-256 61212de872e0e20a…

MALICIOUS

Office (OLE) / .XLS

41.0 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel
MD5: 31e8ef8e63758ef37d3d32c8ba6872a4 SHA-1: a182c02b653a50a3aa711a1c6a7d8cbc9b54cdbd SHA-256: 61212de872e0e20afc55c89891f23ff1395db14cc0d38b3e7070dc6a0699aef4
140 Risk Score

Malware Insights

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

The file is an Excel 4.0 macro-enabled spreadsheet. Heuristics indicate the presence of an Auto_Open function, which is a common technique for executing malicious code upon opening the document. The macro sheet contains references to dangerous formula APIs, including 'RUN', suggesting it is designed to execute external commands or download payloads. No specific IOCs like 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
351469a6991ef12f59ca422d85d2e49c37916f7ca39ced18e999cfdc64abd545
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 7915 bytes