Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 f537f5528456be25…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-27 11:44:37 Authoring application: Microsoft Excel First seen: 2021-10-12
MD5: cb65477419ec77f488e30a875374a308 SHA-1: 5ceb06bf3748806245b94a5677337b200470bd9f SHA-256: f537f5528456be2501494ad4f0296ebdf8543ede577fa8f024045800bf64d3ec
140 Risk Score

Malware Insights

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

The file contains Excel 4.0 (XLM) macros, specifically an Auto_Open entry, which is a critical finding. The presence of dangerous formula APIs within the Auto_Open function indicates an intent to execute arbitrary code. While the exact payload is not discernible from the provided evidence, the mechanism strongly suggests an attempt to exploit the Excel application for malicious purposes.

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) 6847 bytes
SHA-256: 1aff1a12f8b9ad8fae83c1503e25ff419ecbfed7ea37fdaaef765a1a033fcd38
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     20 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  ImrrtocNGVi
' 0018     25 LABEL : Cell Value, String Constant - AATUQHFAev len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!F141 
' 0018     26 LABEL : Cell Value, String Constant - dZuOBTBaoLp len=0 
' 0018     23 LABEL : Cell Value, String Constant - FtrISqHO len=0 
' 0018     23 LABEL : Cell Value, String Constant - JgyVGIse len=0 
' 0018     23 LABEL : Cell Value, String Constant - JPxjbQrP len=0 
' 0018     25 LABEL : Cell Value, String Constant - LVjLdWjqlh len=0 
' 0018     20 LABEL : Cell Value, String Constant - mTymf len=0 
' 0018     26 LABEL : Cell Value, String Constant - PYBzSDaZLBu len=0 
' 0018     22 LABEL : Cell Value, String Constant - qvgIqjm len=0 
' 0018     27 LABEL : Cell Value, String Constant - RKPaSqMWtAbI len=0 
' 0018     24 LABEL : Cell Value, String Constant - sWjvoRfIx len=0 
' 0018     21 LABEL : Cell Value, String Constant - UfKWhQ len=0 
' 0018     26 LABEL : Cell Value, String Constant - UgCAcyBevpR len=0 
' 0018     20 LABEL : Cell Value, String Constant - UmezV len=0 
' 0018     25 LABEL : Cell Value, String Constant - viLdZbtkLw len=0 
' 0018     20 LABEL : Cell Value, String Constant - VRaom len=0 
' 0018     26 LABEL : Cell Value, String Constant - WwgztaHxtZu len=0 
' 0018     20 LABEL : Cell Value, String Constant - YxrIb len=0 
' 0018     23 LABEL : Cell Value, String Constant - YzSbUtUQ len=0 
' 0018     20 LABEL : Cell Value, String Constant - Zyomi 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.