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

Static analysis result for SHA-256 9cc5c75c665dc134…

MALICIOUS

Office (OLE) / .XLS

36.5 KB Created: 2020-11-27 11:43:00 Authoring application: Microsoft Excel First seen: 2022-04-23
MD5: feda5ab63c1e053419e68ae79f0edae8 SHA-1: 8b18c194ffd07fe30e4f534dfe6a1d1090d7dedd SHA-256: 9cc5c75c665dc1343cb12859f8f825d8d9ea292b09da0d444cb20687c075984f
140 Risk Score

Malware Insights

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

The file is an Excel 4.0 (XLM) macro-enabled spreadsheet. Critical heuristics indicate the presence of an Auto_Open defined name and the use of dangerous formula APIs, specifically the 'RUN' function. This suggests the macro is designed to execute arbitrary commands upon opening. No specific URLs or hashes were extracted, but the presence of the Auto_Open function and the 'RUN' API strongly indicates a malicious intent to download and execute a second-stage 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
a5b925f37a59db2b50010058c48a3de02aa727747c938c55b34d30815bc41fac		 xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6748 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.