Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 fdace83b655cc048…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:40:51 Authoring application: Microsoft Excel First seen: 2021-10-23
MD5: ab78b7f3a54d3acf6e9ffa3d2dca3796 SHA-1: 3a0a500b417e04dbea000f9ab94bc8157d788213 SHA-256: fdace83b655cc0488af79928a7a77461721fa5e4b9dc4830a6e9d342d1b35443
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 document detected with critical heuristics for Auto_Open execution and dangerous formula APIs. The presence of an Auto_Open entry indicates that the macro will execute automatically upon opening the workbook, which is a common technique for delivering malware. The specific formulas used are not fully detailed but are flagged as dangerous, suggesting they are used for code execution or payload retrieval.

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) 6718 bytes
SHA-256: 0aceab3fb2b14c2678a8839c08abc41c9de65620490cf20bbe3de1f088e7c0d0
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     20 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  NbuETPzHJIA
' 0018     24 LABEL : Cell Value, String Constant - AfDAUHxbg len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!I142 
' 0018     26 LABEL : Cell Value, String Constant - CWIdLdaPOKg len=0 
' 0018     24 LABEL : Cell Value, String Constant - EQBLCjQcD len=0 
' 0018     22 LABEL : Cell Value, String Constant - GQnBlLH len=0 
' 0018     27 LABEL : Cell Value, String Constant - GvxnwMGFmLBL len=0 
' 0018     22 LABEL : Cell Value, String Constant - HJnvQPp len=0 
' 0018     27 LABEL : Cell Value, String Constant - iBjuTaiwrrve len=0 
' 0018     20 LABEL : Cell Value, String Constant - JhtUZ len=0 
' 0018     26 LABEL : Cell Value, String Constant - kKVDQUgGnXL len=0 
' 0018     20 LABEL : Cell Value, String Constant - lAhgJ len=0 
' 0018     21 LABEL : Cell Value, String Constant - NIRzOX len=0 
' 0018     25 LABEL : Cell Value, String Constant - pHfBpMNLHT len=0 
' 0018     26 LABEL : Cell Value, String Constant - pOrLTzaUWXI len=0 
' 0018     27 LABEL : Cell Value, String Constant - ppROfJxwiquA len=0 
' 0018     20 LABEL : Cell Value, String Constant - PyTvq len=0 
' 0018     24 LABEL : Cell Value, String Constant - SWvqGtDjU len=0 
' 0018     27 LABEL : Cell Value, String Constant - SXyQtWuAEVWi len=0 
' 0018     23 LABEL : Cell Value, String Constant - TOEKQiyF len=0 
' 0018     22 LABEL : Cell Value, String Constant - WFolKaM len=0 
' 0018     25 LABEL : Cell Value, String Constant - ZXjLUSxlir 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/ S
... (truncated)

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