Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 978708d1b025c0a9…

MALICIOUS

Office (OLE)

36.5 KB Created: 2020-11-27 11:38:44 Authoring application: Microsoft Excel First seen: 2021-09-16
MD5: 23ab118b763bf35d9114a428b1209fda SHA-1: 42866b9b06fd652974c8bb151f18d9df76fd7ac6 SHA-256: 978708d1b025c0a9691bf62fa74d5b98865d59f90fe503c0de2f7d530db46896
140 Risk Score

Malware Insights

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

The file is an Excel document containing Excel 4.0 macros, indicated by the OLE_XLM_AUTOOPEN and OLE_XLM_DANGEROUS_FN heuristics. The presence of an Auto_Open defined name suggests that the macro will execute automatically when the workbook is opened. The dangerous formula APIs used in the macro indicate it is designed to perform malicious actions, such as downloading and executing a secondary 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) 6682 bytes
SHA-256: 84a5961708c663b002ffa68f7f543a7435c5170ba8cab7d44909102b5ba2e910
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 -  byRzi
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!F134 
' 0018     20 LABEL : Cell Value, String Constant - AVEHJ len=0 
' 0018     25 LABEL : Cell Value, String Constant - bSqQzwJfQL len=0 
' 0018     21 LABEL : Cell Value, String Constant - EXjSXX len=0 
' 0018     23 LABEL : Cell Value, String Constant - fQcFaXGO len=0 
' 0018     22 LABEL : Cell Value, String Constant - GanaiBm len=0 
' 0018     20 LABEL : Cell Value, String Constant - GTVni len=0 
' 0018     27 LABEL : Cell Value, String Constant - HKlOYQfrmBcK len=0 
' 0018     25 LABEL : Cell Value, String Constant - iXicrBsAPk len=0 
' 0018     21 LABEL : Cell Value, String Constant - JarUnp len=0 
' 0018     21 LABEL : Cell Value, String Constant - JOjvpO len=0 
' 0018     24 LABEL : Cell Value, String Constant - kAkvSSQDU len=0 
' 0018     22 LABEL : Cell Value, String Constant - lJbOYwA len=0 
' 0018     27 LABEL : Cell Value, String Constant - LKmgTTJbQWEP len=0 
' 0018     26 LABEL : Cell Value, String Constant - MdHdcWxlrDb len=0 
' 0018     23 LABEL : Cell Value, String Constant - nXYfYROx len=0 
' 0018     27 LABEL : Cell Value, String Constant - owoQovnXYNhx len=0 
' 0018     25 LABEL : Cell Value, String Constant - WdEbgrRDph len=0 
' 0018     25 LABEL : Cell Value, String Constant - XqbPmtqPpF len=0 
' 0018     26 LABEL : Cell Value, String Constant - xvlmFabqASx len=0 
' 0018     22 LABEL : Cell Value, String Constant - Yktqotf 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   
... (truncated)

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