Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 3607b595c3fbea6a…

MALICIOUS

Office (OLE)

36.5 KB Created: 2020-11-27 11:39:05 Authoring application: Microsoft Excel First seen: 2021-09-25
MD5: 1c0d11f5670fcdd604b1c12d59920548 SHA-1: 0909a8c30b819e6d11e40e1b8010ad55cf4f1c41 SHA-256: 3607b595c3fbea6a1d8e8eff7239d16b622757a641772bd951e87dfab4718f7c
140 Risk Score

Malware Insights

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

The file contains Excel 4.0 (XLM) macros, specifically an Auto_Open defined name, which is a critical finding. This indicates an attempt to automatically execute code upon opening the document. The presence of dangerous formula APIs further suggests malicious intent, likely to download and execute a second-stage payload.

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) 6709 bytes
SHA-256: b9808b818397745d89f31468d7b500ae7cece9310f5624004465ee8fcb81ebb4
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     16 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  aYLzQat
' 0018     23 LABEL : Cell Value, String Constant - aLfLLQsj len=0 
' 0018     27 LABEL : Cell Value, String Constant - AnumgFASLDwH len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!F192 
' 0018     20 LABEL : Cell Value, String Constant - Bcryj len=0 
' 0018     20 LABEL : Cell Value, String Constant - bCwhq len=0 
' 0018     25 LABEL : Cell Value, String Constant - bFEfRMqTTP len=0 
' 0018     27 LABEL : Cell Value, String Constant - csgnzMFpNZyq len=0 
' 0018     25 LABEL : Cell Value, String Constant - iExDPlnBze len=0 
' 0018     24 LABEL : Cell Value, String Constant - KrEvxQsKP len=0 
' 0018     21 LABEL : Cell Value, String Constant - RckGag len=0 
' 0018     23 LABEL : Cell Value, String Constant - SRGkiFFk len=0 
' 0018     23 LABEL : Cell Value, String Constant - tcWCUYWQ len=0 
' 0018     22 LABEL : Cell Value, String Constant - tDaFpLC len=0 
' 0018     25 LABEL : Cell Value, String Constant - TLkwSGEJST len=0 
' 0018     23 LABEL : Cell Value, String Constant - uiOVTPhy len=0 
' 0018     20 LABEL : Cell Value, String Constant - wnaPu len=0 
' 0018     24 LABEL : Cell Value, String Constant - WTmrhdXKJ len=0 
' 0018     24 LABEL : Cell Value, String Constant - XdyAKfunM len=0 
' 0018     20 LABEL : Cell Value, String Constant - yGHRj len=0 
' 0018     27 LABEL : Cell Value, String Constant - yVFMklHiwigR len=0 
' 0018     22 LABEL : Cell Value, String Constant - zcnIOCJ 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 
... (truncated)

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