Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 3e41bcc6bceff6a8…

MALICIOUS

Office (OLE)

31.0 KB Created: 2021-01-28 13:54:16 Authoring application: Microsoft Excel First seen: 2021-02-19
MD5: 13b75a30e9f873db2fbf8d6791def6d2 SHA-1: 059c9e0a79eb43fb96588175e2f0fb4d1c8d9609 SHA-256: 3e41bcc6bceff6a80a6b4f60e0e5fec9ed6e6eb63497326d7066e78dbe5139bb
160 Risk Score

Heuristics 4

  • 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.
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

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) 3450 bytes
SHA-256: 1d8c71bddddfff23698648e1aa3dc1ab56b834b29b31ff3f7bd5761dbedce138
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     18 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  LdqMbGxUF
' 0018     21 LABEL : Cell Value, String Constant - aEmGjD len=0 
' 0018    557 LABEL : Cell Value, String Constant - aSaNa len=8 ptgArrayA  *INCOMPLETE FORMULA PARSING* Remaining, unparsed expression: b'\x00\x11\x00\x00\x00\x00\x00'
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!C136 
' 0018     27 LABEL : Cell Value, String Constant - fJQuS len=7 ptgRef3d  LdqMbGxUF!F43 
' 0018     22 LABEL : Cell Value, String Constant - FzAn len=3 ptgInt 0 
' 0018     24 LABEL : Cell Value, String Constant - hKCBGW len=3 ptgInt 0 
' 0018     26 LABEL : Cell Value, String Constant - IHAG len=7 ptgRef3d  LdqMbGxUF!I48 
' 0018     27 LABEL : Cell Value, String Constant - JHtkU len=7 ptgRef3d  LdqMbGxUF!A42 
' 0018     30 LABEL : Cell Value, String Constant - JpMBgRyG len=7 ptgRef3d  LdqMbGxUF!C53 
' 0018     27 LABEL : Cell Value, String Constant - JWBPn len=7 ptgRef3d  LdqMbGxUF!G55 
' 0018     27 LABEL : Cell Value, String Constant - kPbkc len=7 ptgRef3d  LdqMbGxUF!D40 
' 0018     32 LABEL : Cell Value, String Constant - lbvWHtMyqH len=7 ptgRef3d  Sheet!C78 
' 0018     22 LABEL : Cell Value, String Constant - mUeW len=3 ptgInt 0 
' 0018     23 LABEL : Cell Value, String Constant - NZvMk len=3 ptgInt 0 
' 0018     29 LABEL : Cell Value, String Constant - orJnDFV len=7 ptgRef3d  LdqMbGxUF!H45 
' 0018     29 LABEL : Cell Value, String Constant - polITZH len=7 ptgRef3d  LdqMbGxUF!B48 
' 0018    123 LABEL : Cell Value, String Constant - RqvZcyg len=8 ptgArrayA  *INCOMPLETE FORMULA PARSING* Remaining, unparsed expression: b'\x00\t\x00\x00\x00\x00\x00'
' 0018     27 LABEL : Cell Value, String Constant - TITYp len=7 ptgRef3d  LdqMbGxUF!E58 
' 0018     27 LABEL : Cell Value, String Constant - vsVWB len=7 ptgRef3d  LdqMbGxUF!J41 
' 0018   2035 LABEL : Cell Value, String Constant - yFfad len=8 ptgArrayA  *INCOMPLETE FORMULA PARSING* Remaining, unparsed expression: b'\x00%\x00\x00\x00\x00\x00'
' 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
' 002a      2 PRINTHEADERS : Print Row/Column Labels
' Sheet,Reference,Formula,Value
'  Sheet,D39,"ABC",""
'  Sheet,D40,[],""
'  Sheet,J40,"ABC",""
'  Sheet,A41,"ABC",""
'  Sheet,J41,[],""
'  Sheet,A42,ROWS(aSaNa),""
'  Sheet,F42,"ABC",""
'  Sheet,F43,[],""
'  Sheet,H44,"ABC",""
'  Sheet,H45,[],""
'  Sheet,B47,"ABC",""
'  Sheet,I47,"ABC",""
'  Sheet,B48,ROWS(RqvZcyg),""
'  Sheet,I48,[],""
'  Sheet,C52,"ABC",""
'  Sheet,C53,aSaNa,""
'  Sheet,G54,"ABC",""
'  Sheet,G55,RqvZcyg,""
'  Sheet,E57,"ABC",""
'  Sheet,E58,[],""
'  LdqMbGxUF,C81,"A"&"B",""
'  LdqMbGxUF,C82,[],""
'  LdqMbGxUF,C86,"SET.VALUE(C119,"")",""
'  LdqMbGxUF,C91,"mUeW",""
'  LdqMbGxUF,C96,"DEFINE.NAME("hKCBGW",0)",""
'  LdqMbGxUF,C100,[],""
'  LdqMbGxUF,C103,"hKCBGW",""
'  LdqMbGxUF,C107,"['C119', 'C119']",""
'  LdqMbGxUF,C111,"FzAn",""
'  LdqMbGxUF,C115,NEXT(),""
'  LdqMbGxUF,C121,"['C119', '"LdqMbGxUFR!R"']",""
'  LdqMbGxUF,C125,"aEmGjD",""
'  LdqMbGxUF,C130,NEXT(),""
'  LdqMbGxUF,C133,RETURN(),""
'  LdqMbGxUF,C138,"DEFINE.NAME("aEmGjD",148)",""
'  LdqMbGxUF,C147,lbvWHtMyqH(),""
'  LdqMbGxUF,C148,HALT(),""