Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 3f270bd02d422912…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-27 11:45:07 Authoring application: Microsoft Excel First seen: 2021-10-07
MD5: f38ae1dbd2f98dd071f3b476bcb481cb SHA-1: 5167aed7de92692a8a0f7442d4854d4aa167da17 SHA-256: 3f270bd02d422912a8ee6289116a306c8c71bad01ac35fcea6222d5876cdebd1
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 external code. While the exact payload is not visible, the pattern strongly suggests a downloader or initial execution stage for a more complex attack.

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) 6556 bytes
SHA-256: 85f15b58d46b4bfa3f33bac0c59e54cb817f5dc8af921d689f48aa19a5c59a7a
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 -  npDY
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!C156 
' 0018     27 LABEL : Cell Value, String Constant - BpLbFZJtuvhj len=0 
' 0018     22 LABEL : Cell Value, String Constant - CMUkmds len=0 
' 0018     21 LABEL : Cell Value, String Constant - dcMquk len=0 
' 0018     21 LABEL : Cell Value, String Constant - Dshzpo len=0 
' 0018     20 LABEL : Cell Value, String Constant - gjOXk len=0 
' 0018     20 LABEL : Cell Value, String Constant - hmPZg len=0 
' 0018     25 LABEL : Cell Value, String Constant - IvDISzigfb len=0 
' 0018     25 LABEL : Cell Value, String Constant - JzePeynBZZ len=0 
' 0018     21 LABEL : Cell Value, String Constant - kaVtYT len=0 
' 0018     25 LABEL : Cell Value, String Constant - KlECHGvUKM len=0 
' 0018     20 LABEL : Cell Value, String Constant - LPCCJ len=0 
' 0018     22 LABEL : Cell Value, String Constant - NJRzEBl len=0 
' 0018     23 LABEL : Cell Value, String Constant - OVeQMpJM len=0 
' 0018     26 LABEL : Cell Value, String Constant - RxjrhXTSbit len=0 
' 0018     22 LABEL : Cell Value, String Constant - SqaMxaf len=0 
' 0018     24 LABEL : Cell Value, String Constant - SQdcZpRqQ len=0 
' 0018     25 LABEL : Cell Value, String Constant - syDFegaazR len=0 
' 0018     26 LABEL : Cell Value, String Constant - uVKKldFMNFW len=0 
' 0018     25 LABEL : Cell Value, String Constant - wGAVZKDKmg len=0 
' 0018     20 LABEL : Cell Value, String Constant - xNBYO 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)

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