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

Static analysis result for SHA-256 2c3828aa5c49e22f…

MALICIOUS

Office (OLE) / .XLS

25.5 KB Created: 2026-06-16 11:11:34 Authoring application: Microsoft Excel First seen: 2026-06-19
MD5: f68dcb5b89d45fc55ef3949ca0646757 SHA-1: 4a90a4006069a179d22259a6ef653ac0f3990858 SHA-256: 2c3828aa5c49e22f1e6894fb4f42c241ddd38a6f3a53e6ba76b7353ce1403114
140 Risk Score

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 xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 536 bytes
SHA-256: bf8c59d6fd1902c736de86b1aff84736318568359dd41fb9ea9be46454e71930
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, very hidden -  Macro
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Macro!A1 
' 002a      2 PRINTHEADERS : Print Row/Column Labels
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 002a      2 PRINTHEADERS : Print Row/Column Labels
' Sheet,Reference,Formula,Value
'  Macro,A1,EXEC("calc.exe"),""
'  Macro,A2,HALT(),""