Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 f372f1ea4b6f171f…

MALICIOUS

Office (OLE)

37.0 KB Created: 2020-11-25 10:44:25 Authoring application: Microsoft Excel First seen: 2021-09-27
MD5: 994ce1664abc85c097220673667f6f27 SHA-1: fabe00b605b1634e5890d0df1def2cf21ac00a11 SHA-256: f372f1ea4b6f171fa653db57dafe4ee50a7e75d684fed709dc0e64cd14ab881c
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-enabled workbook. Static analysis detected an Auto_Open defined name, which is a common technique for automatically executing malicious code upon opening the workbook. The presence of dangerous formula APIs in the Auto_Open macro suggests an intent to perform actions beyond standard spreadsheet operations, likely leading to further execution.

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) 6471 bytes
SHA-256: 18904462b799020f6083b4b7f55d0354946cee1d064b78c9f97336d884092482
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     12 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  NxD
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!F141 
' 0018     22 LABEL : Cell Value, String Constant - cbmoGDi len=0 
' 0018     20 LABEL : Cell Value, String Constant - CjmuF len=0 
' 0018     23 LABEL : Cell Value, String Constant - cojixyIC len=0 
' 0018     24 LABEL : Cell Value, String Constant - hmYTpIdlU len=0 
' 0018     24 LABEL : Cell Value, String Constant - kQzWMyUcP len=0 
' 0018     22 LABEL : Cell Value, String Constant - MYPlFhA len=0 
' 0018     23 LABEL : Cell Value, String Constant - NnIRnfcM len=0 
' 0018     26 LABEL : Cell Value, String Constant - ocmQULvaXYD len=0 
' 0018     20 LABEL : Cell Value, String Constant - OnpGs len=0 
' 0018     24 LABEL : Cell Value, String Constant - RfBAplWzy len=0 
' 0018     22 LABEL : Cell Value, String Constant - SoddqRm len=0 
' 0018     27 LABEL : Cell Value, String Constant - stJhlpMOHvkO len=0 
' 0018     24 LABEL : Cell Value, String Constant - uzanHFDjN len=0 
' 0018     22 LABEL : Cell Value, String Constant - vcvbzgt len=0 
' 0018     20 LABEL : Cell Value, String Constant - vmCHs len=0 
' 0018     25 LABEL : Cell Value, String Constant - XuhvTYqeBU len=0 
' 0018     22 LABEL : Cell Value, String Constant - yhWCXHP len=0 
' 0018     26 LABEL : Cell Value, String Constant - YMnpZxLLYgL len=0 
' 0018     24 LABEL : Cell Value, String Constant - YPAqKvlnR len=0 
' 0018     21 LABEL : Cell Value, String Constant - zLJPFp 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.