Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 517524c13a0826e4…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-27 11:41:02 Authoring application: Microsoft Excel First seen: 2021-11-02
MD5: 908ef557676c78e0b850eb34e2816170 SHA-1: 2d8bb4a381774e4309adb1175e0648903b910b8a SHA-256: 517524c13a0826e4e356ed0c94f0d257ad79afc15dfa8e708c6ce42feed56f8a
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 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 arbitrary code. This is a common technique for downloading and executing further malicious payloads.

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) 6604 bytes
SHA-256: b5bf57fff9e51ae0e5513c27d30ff4842b6f42d9e9b6adc1ccc8b800aa5a35d0
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 -  bIPB
' 0018     23 LABEL : Cell Value, String Constant - aHlubVeC len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!E159 
' 0018     22 LABEL : Cell Value, String Constant - BjhQhff len=0 
' 0018     24 LABEL : Cell Value, String Constant - bLuUuwjsf len=0 
' 0018     23 LABEL : Cell Value, String Constant - CEoMHXgq len=0 
' 0018     25 LABEL : Cell Value, String Constant - EsrJWeWeqD len=0 
' 0018     21 LABEL : Cell Value, String Constant - GZCRbs len=0 
' 0018     22 LABEL : Cell Value, String Constant - gZShQTs len=0 
' 0018     27 LABEL : Cell Value, String Constant - jngrnpmFkWTj len=0 
' 0018     25 LABEL : Cell Value, String Constant - lQGOrSAEdv len=0 
' 0018     22 LABEL : Cell Value, String Constant - pHTmxJW len=0 
' 0018     21 LABEL : Cell Value, String Constant - PvmcXx len=0 
' 0018     24 LABEL : Cell Value, String Constant - PzzqCqKzj len=0 
' 0018     20 LABEL : Cell Value, String Constant - SpslW len=0 
' 0018     26 LABEL : Cell Value, String Constant - SquxnpLBdcl len=0 
' 0018     24 LABEL : Cell Value, String Constant - taYbQQXMO len=0 
' 0018     20 LABEL : Cell Value, String Constant - TeBCD len=0 
' 0018     27 LABEL : Cell Value, String Constant - xqLchsMxYLfm len=0 
' 0018     25 LABEL : Cell Value, String Constant - YEITxxeJWs len=0 
' 0018     25 LABEL : Cell Value, String Constant - yXxdNHGSDW len=0 
' 0018     26 LABEL : Cell Value, String Constant - ZVTvhsncWvb 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.