Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 a9c71c1d6259e18b…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:46:16 Authoring application: Microsoft Excel First seen: 2021-05-22
MD5: fa1764d1a0252e3e3ca4ce93cc49d9ed SHA-1: 742f45dce98d5339d5567109cc045d644a4f9430 SHA-256: a9c71c1d6259e18b87e22646df67cfbb72f8bd35941462333eaadd60700422d5
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 workbook containing an Auto_Open macro. This macro is designed to execute arbitrary code upon opening, leveraging dangerous formula APIs. The presence of an Auto_Open entry in an XLM macro sheet indicates a direct execution path for malicious commands.

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) 6586 bytes
SHA-256: f18e44a87f30909668aa2ac96fb21f1ecbab0df27b7d17675456141166e2b26c
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     18 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  duejPOWJi
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!I136 
' 0018     21 LABEL : Cell Value, String Constant - csWJpR len=0 
' 0018     27 LABEL : Cell Value, String Constant - DNTKwnyGcdqu len=0 
' 0018     27 LABEL : Cell Value, String Constant - elugeYVQvApn len=0 
' 0018     27 LABEL : Cell Value, String Constant - gJbHNyzwrdoc len=0 
' 0018     26 LABEL : Cell Value, String Constant - hteStfFMVSM len=0 
' 0018     21 LABEL : Cell Value, String Constant - htiYEY len=0 
' 0018     20 LABEL : Cell Value, String Constant - ikpaK len=0 
' 0018     24 LABEL : Cell Value, String Constant - jGfTzTbmq len=0 
' 0018     21 LABEL : Cell Value, String Constant - JzXrVT len=0 
' 0018     24 LABEL : Cell Value, String Constant - llRrtsIcv len=0 
' 0018     27 LABEL : Cell Value, String Constant - PgOAkHRqZgBh len=0 
' 0018     27 LABEL : Cell Value, String Constant - PUJvYILdLVCf len=0 
' 0018     22 LABEL : Cell Value, String Constant - PxCEiHa len=0 
' 0018     22 LABEL : Cell Value, String Constant - RVYWMsb len=0 
' 0018     25 LABEL : Cell Value, String Constant - vHzPtQhXFJ len=0 
' 0018     27 LABEL : Cell Value, String Constant - WaLTcKXSlPxW len=0 
' 0018     20 LABEL : Cell Value, String Constant - wJTMH len=0 
' 0018     23 LABEL : Cell Value, String Constant - WLiVNrtF len=0 
' 0018     26 LABEL : Cell Value, String Constant - WtRDOTNYbCo len=0 
' 0018     25 LABEL : Cell Value, String Constant - yZMjjulTbB 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/
... (truncated)

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