Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 603039e8c05c2b94…

MALICIOUS

Office (OLE)

35.5 KB Created: 2020-11-25 10:43:12 Authoring application: Microsoft Excel First seen: 2021-09-25
MD5: 66cf3b88824a1b2662d343f01724901e SHA-1: 3f810afc17e8423882d61b48493225fb9503e954 SHA-256: 603039e8c05c2b94fef409b236226ab59e2f08fc0dfc3893d0d4e939b4855297
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 sheet containing an Auto_Open function, which is a critical indicator of malicious intent. This function is designed to execute automatically when the workbook is opened, and the presence of dangerous formula APIs like RUN suggests it's intended to download and execute a secondary payload. No specific family could be identified from the available evidence.

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) 6376 bytes
SHA-256: 4adc02b9b18ae3316c2887dfc31082e4f0d98ee7bac5efc848af51a7990273db
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 -  nxJQ
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!G199 
' 0018     26 LABEL : Cell Value, String Constant - bIOvaCjJgvw len=0 
' 0018     24 LABEL : Cell Value, String Constant - CpRFGqTuR len=0 
' 0018     25 LABEL : Cell Value, String Constant - ekyUwRLfIs len=0 
' 0018     26 LABEL : Cell Value, String Constant - gqqljzSfNAH len=0 
' 0018     22 LABEL : Cell Value, String Constant - gZoxKOl len=0 
' 0018     25 LABEL : Cell Value, String Constant - hPCQMomgWB len=0 
' 0018     21 LABEL : Cell Value, String Constant - iSUABV len=0 
' 0018     20 LABEL : Cell Value, String Constant - KOWqk len=0 
' 0018     27 LABEL : Cell Value, String Constant - mrLJpQZnMMrr len=0 
' 0018     27 LABEL : Cell Value, String Constant - OwWFHhDzkHKL len=0 
' 0018     22 LABEL : Cell Value, String Constant - QhIyHWw len=0 
' 0018     22 LABEL : Cell Value, String Constant - TKSFJMH len=0 
' 0018     20 LABEL : Cell Value, String Constant - ubVeD len=0 
' 0018     20 LABEL : Cell Value, String Constant - UyonG len=0 
' 0018     23 LABEL : Cell Value, String Constant - vjCZcBzN len=0 
' 0018     22 LABEL : Cell Value, String Constant - VPpwvBY len=0 
' 0018     21 LABEL : Cell Value, String Constant - vtJFBQ len=0 
' 0018     25 LABEL : Cell Value, String Constant - xgfhvFIIJe len=0 
' 0018     20 LABEL : Cell Value, String Constant - yjmQD len=0 
' 0018     21 LABEL : Cell Value, String Constant - ytWtGa 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.