Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 e9779c2b821e982e…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:47:20 Authoring application: Microsoft Excel
MD5: ad11a37732383c003afc9fd473705245 SHA-1: bd2e7cf00082f7b09daed3e2b5dd86559651206a SHA-256: e9779c2b821e982e7d53661ce22b91dc67ea518f433a4309d84bd9a4ae408571
140 Risk Score

Malware Insights

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

This Excel file contains Excel 4.0 macros, specifically an Auto_Open function, which is a known technique for executing malicious code. The critical heuristics indicate the presence of dangerous formula APIs within the Auto_Open macro, suggesting it is designed to download and execute a secondary payload. No specific family could be identified, and no direct IOCs like URLs or hashes were extracted from the macro content itself.

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
5a4e9da5ec6d3b038ccf9b186c8077ebca24e71b8536aa91443621d475da1ceb
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6417 bytes