Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 a792092cda8f0a13…

MALICIOUS

Office (OLE)

36.5 KB Created: 2020-11-25 10:45:46 Authoring application: Microsoft Excel
MD5: a5acbd9be839847d8352f407dcbcba30 SHA-1: 2fd5567578d9696b860fbace914b00848d0bc450 SHA-256: a792092cda8f0a133167653a7c5cf53f7de0f26fc8d0ffa0fb052c8a91a2e01b
140 Risk Score

Malware Insights

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

The critical heuristics indicate the presence of Excel 4.0 macros with an Auto_Open entry, which is a common method for executing malicious code upon opening the workbook. The macro sheet contains formulas that call dangerous API functions, including 'RUN', suggesting it is designed to execute external code. No specific URLs or further payloads were extracted, but the technique strongly implies a downloader or initial execution stage.

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
3ba5cf99a2716136187f89e2c296dccde8e3a6f0cdc7262f0dfcdc9c541c6e34
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6522 bytes