Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 1eaf9e4f42b33932…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-27 11:41:54 Authoring application: Microsoft Excel First seen: 2021-09-25
MD5: a2b607700b838a019ebd0fe71861eec0 SHA-1: 4fba0e6aea2916d2e9afdd08e48bff6cf8b7da52 SHA-256: 1eaf9e4f42b33932a6b5ee5f92e8f1f588d1accbd6599cdb6390734949c52cfc
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 defined name, which is a critical finding indicating automatic execution upon opening. The presence of dangerous formula APIs like RUN suggests the macro is designed to execute arbitrary code. This functionality is commonly used to download and execute a second-stage payload, making the initial file a downloader.

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) 6645 bytes
SHA-256: 6a2320659c70a96512f55b93095139e361b7b0a78e9b2827c5568c2f6d0aafd7
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     14 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  akXOe
' 0018     25 LABEL : Cell Value, String Constant - aHqnphLvxy len=0 
' 0018     20 LABEL : Cell Value, String Constant - AmmMy len=0 
' 0018     20 LABEL : Cell Value, String Constant - AsCkg len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!F141 
' 0018     25 LABEL : Cell Value, String Constant - BdxItBCMrt len=0 
' 0018     21 LABEL : Cell Value, String Constant - bgjDBb len=0 
' 0018     22 LABEL : Cell Value, String Constant - cstVwui len=0 
' 0018     25 LABEL : Cell Value, String Constant - FlZHJqpFpo len=0 
' 0018     24 LABEL : Cell Value, String Constant - icUgtQvzX len=0 
' 0018     24 LABEL : Cell Value, String Constant - iWiBQyEHC len=0 
' 0018     27 LABEL : Cell Value, String Constant - JqeCQIWlvPGl len=0 
' 0018     21 LABEL : Cell Value, String Constant - KkRdaP len=0 
' 0018     22 LABEL : Cell Value, String Constant - kpAmHhI len=0 
' 0018     24 LABEL : Cell Value, String Constant - MwiwAscDZ len=0 
' 0018     25 LABEL : Cell Value, String Constant - qGohPLsJaJ len=0 
' 0018     27 LABEL : Cell Value, String Constant - vuEthSTtYUot len=0 
' 0018     26 LABEL : Cell Value, String Constant - wfVvJuGlpIK len=0 
' 0018     22 LABEL : Cell Value, String Constant - xxEQPcq len=0 
' 0018     27 LABEL : Cell Value, String Constant - yOzwdrBeGUpM len=0 
' 0018     24 LABEL : Cell Value, String Constant - ZfLJTlyaN len=0 
' 0018     25 LABEL : Cell Value, String Constant - ZimokfRBdj 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
' 00f
... (truncated)

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