Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 84bd5d153e9f2f2f…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:35:28 Authoring application: Microsoft Excel First seen: 2021-10-02
MD5: 0c3ca3a665ddf2b8cee98380b1611978 SHA-1: a9d33a6ccc0ecd7b523fafd043fe8aff15e393a5 SHA-256: 84bd5d153e9f2f2f2d429c60cb62994a59485d5711c6b17bd197626b46fd08c3
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 workbook containing an Auto_Open function, which is a critical finding indicating automatic execution upon opening. The presence of dangerous formula APIs like RUN suggests the macro is designed to execute arbitrary code, likely downloading and running a second-stage payload. No specific family could be identified, but the technique is common for initial payload delivery.

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) 6579 bytes
SHA-256: 37467f9ece562fc77ced8ff9b51955e03ee265d712afe04d81f7d5802c51b120
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     15 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  WFGldN
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!B152 
' 0018     23 LABEL : Cell Value, String Constant - bpJfYegY len=0 
' 0018     24 LABEL : Cell Value, String Constant - bvfHcdxzq len=0 
' 0018     21 LABEL : Cell Value, String Constant - ckxXWC len=0 
' 0018     27 LABEL : Cell Value, String Constant - cncmGjsgtSxF len=0 
' 0018     21 LABEL : Cell Value, String Constant - CRMVIy len=0 
' 0018     27 LABEL : Cell Value, String Constant - DNxnaQPrRUFe len=0 
' 0018     26 LABEL : Cell Value, String Constant - dpTBGJFpmPg len=0 
' 0018     22 LABEL : Cell Value, String Constant - EDSKzRd len=0 
' 0018     26 LABEL : Cell Value, String Constant - EPDuOraRrwZ len=0 
' 0018     27 LABEL : Cell Value, String Constant - gaANkxzNYSgk len=0 
' 0018     27 LABEL : Cell Value, String Constant - JFZuHWuqPSvF len=0 
' 0018     23 LABEL : Cell Value, String Constant - kdPVVfet len=0 
' 0018     25 LABEL : Cell Value, String Constant - KwpiZnskNb len=0 
' 0018     26 LABEL : Cell Value, String Constant - oXeNwwVpZMy len=0 
' 0018     26 LABEL : Cell Value, String Constant - pTPfKxVLHdA len=0 
' 0018     25 LABEL : Cell Value, String Constant - QCTUvrSpPL len=0 
' 0018     20 LABEL : Cell Value, String Constant - SioHv len=0 
' 0018     25 LABEL : Cell Value, String Constant - vjxDKNwWWd len=0 
' 0018     24 LABEL : Cell Value, String Constant - YuMNFudsa len=0 
' 0018     24 LABEL : Cell Value, String Constant - ZxLVOBiXs len=0 
' 002a      2 PRINTHEADERS : Print Row/Column Labels
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Constant/ SST
' 00fd     10 LABELSST : Cell Value, String Const
... (truncated)

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