Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 1903fcf337bc2fe3…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-27 11:42:47 Authoring application: Microsoft Excel First seen: 2021-10-01
MD5: 265042c3a9c878a0b1774163f97cc9cb SHA-1: 8a278f8eefeced148fb2e08c8252e5fbc2c74227 SHA-256: 1903fcf337bc2fe36ec04c36cf29e391ebf795172f98530068a942b1019bb2d4
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. This indicates the macro sheet is designed to automatically execute code upon opening. The presence of dangerous formula APIs like RUN further suggests an intent to execute arbitrary commands, likely to download and run 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) 6559 bytes
SHA-256: d0cb8b5f29b50377316deb4730227da592adb061cfc9bf520bc27149a62d1fa6
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     13 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  wAXk
' 0018     21 LABEL : Cell Value, String Constant - AcqlOD len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!H141 
' 0018     20 LABEL : Cell Value, String Constant - cfHNP len=0 
' 0018     21 LABEL : Cell Value, String Constant - CMwpAD len=0 
' 0018     23 LABEL : Cell Value, String Constant - CPDGEheZ len=0 
' 0018     26 LABEL : Cell Value, String Constant - DRwxwprkDQh len=0 
' 0018     25 LABEL : Cell Value, String Constant - GDKPtXHlvh len=0 
' 0018     20 LABEL : Cell Value, String Constant - hLnOO len=0 
' 0018     25 LABEL : Cell Value, String Constant - HOmSzMzUia len=0 
' 0018     21 LABEL : Cell Value, String Constant - IEQolN len=0 
' 0018     25 LABEL : Cell Value, String Constant - IkjXCAuBRM len=0 
' 0018     21 LABEL : Cell Value, String Constant - IuSsiq len=0 
' 0018     21 LABEL : Cell Value, String Constant - KcXMdc len=0 
' 0018     25 LABEL : Cell Value, String Constant - ljJflYYDfk len=0 
' 0018     22 LABEL : Cell Value, String Constant - lKYeaje len=0 
' 0018     24 LABEL : Cell Value, String Constant - MWZMMhjxH len=0 
' 0018     20 LABEL : Cell Value, String Constant - njEhC len=0 
' 0018     23 LABEL : Cell Value, String Constant - SyJwxImP len=0 
' 0018     24 LABEL : Cell Value, String Constant - UlvXquxXV len=0 
' 0018     26 LABEL : Cell Value, String Constant - unVnxupNNDX len=0 
' 0018     25 LABEL : Cell Value, String Constant - zfenUuoGgh 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 LABELSST :
... (truncated)

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