Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 da489eaec60bd880…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:25:18 Authoring application: Microsoft Excel First seen: 2021-10-16
MD5: cbc980ae2305fe0f91e79289ffda832f SHA-1: 8db6eb7b80324e3a6de160eb9d68eb9c3c23bea8 SHA-256: da489eaec60bd880d1d53d1d88d24a985c85269a0b1e38724ff868c7e9e9d03e
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 entry point, which is a known method for executing malicious code. The macro sheet itself contains a large amount of obfuscated data, suggesting it is designed to download and execute a secondary payload. The use of dangerous formula APIs like RUN further supports this malicious intent.

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) 6599 bytes
SHA-256: 8b6fc0e383028b4e2a897a7fe8b7f0600160ccaa3984a36a04b79a703c9ebdf2
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     19 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  wNbUgbMHSu
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!D168 
' 0018     22 LABEL : Cell Value, String Constant - BisiRqv len=0 
' 0018     27 LABEL : Cell Value, String Constant - BnCupStgWPOG len=0 
' 0018     22 LABEL : Cell Value, String Constant - cMtFJIn len=0 
' 0018     20 LABEL : Cell Value, String Constant - fgmpW len=0 
' 0018     20 LABEL : Cell Value, String Constant - iKpZM len=0 
' 0018     22 LABEL : Cell Value, String Constant - KWVCxDU len=0 
' 0018     24 LABEL : Cell Value, String Constant - LAQLhipii len=0 
' 0018     20 LABEL : Cell Value, String Constant - LOtlB len=0 
' 0018     20 LABEL : Cell Value, String Constant - Mytfv len=0 
' 0018     23 LABEL : Cell Value, String Constant - OqJTrxll len=0 
' 0018     24 LABEL : Cell Value, String Constant - PbmgRAIeK len=0 
' 0018     26 LABEL : Cell Value, String Constant - pDxLPalSxjy len=0 
' 0018     27 LABEL : Cell Value, String Constant - piBSidjVVYoC len=0 
' 0018     27 LABEL : Cell Value, String Constant - PXUmUnlesQEo len=0 
' 0018     20 LABEL : Cell Value, String Constant - qaJVW len=0 
' 0018     20 LABEL : Cell Value, String Constant - rWHzs len=0 
' 0018     26 LABEL : Cell Value, String Constant - TBwoDYfYiWK len=0 
' 0018     25 LABEL : Cell Value, String Constant - tEejhGNTlr len=0 
' 0018     22 LABEL : Cell Value, String Constant - ttUpRPw len=0 
' 0018     24 LABEL : Cell Value, String Constant - uXBPJbsyD 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 L
... (truncated)

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