Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 05716a93c89070e5…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:46:19 Authoring application: Microsoft Excel First seen: 2021-06-20
MD5: 51d4fd1dd770be3a852daae0da84174c SHA-1: 1f167674d039510d7f2f547589158ee05f475c5e SHA-256: 05716a93c89070e55861cf4f81f4626e64a226437ed06a3072a17c8ac79cc58e
140 Risk Score

Malware Insights

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

The file contains Excel 4.0 macros, specifically an Auto_Open defined name, which is a critical finding. This indicates the macro sheet is designed to execute automatically when the workbook is opened. The presence of dangerous formula APIs like RUN suggests the macro is intended to execute arbitrary commands, likely to download and run a second-stage 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) 6715 bytes
SHA-256: 7ad399d169698451fbefbc92d5af144edc3d067b96c435ed91d9ff3d6034e43e
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 -  SwRAhTBgxSJ
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!H180 
' 0018     21 LABEL : Cell Value, String Constant - CBZqwJ len=0 
' 0018     21 LABEL : Cell Value, String Constant - dlidKf len=0 
' 0018     25 LABEL : Cell Value, String Constant - dlqAAkwnTT len=0 
' 0018     21 LABEL : Cell Value, String Constant - eZhnJm len=0 
' 0018     27 LABEL : Cell Value, String Constant - fquScWkxkjmd len=0 
' 0018     20 LABEL : Cell Value, String Constant - fZeIb len=0 
' 0018     27 LABEL : Cell Value, String Constant - HXxeaSjxGUjR len=0 
' 0018     20 LABEL : Cell Value, String Constant - MSHca len=0 
' 0018     20 LABEL : Cell Value, String Constant - PCTjU len=0 
' 0018     23 LABEL : Cell Value, String Constant - QiKXamHB len=0 
' 0018     25 LABEL : Cell Value, String Constant - QJEaJXEXVt len=0 
' 0018     26 LABEL : Cell Value, String Constant - QOwiyLGJyik len=0 
' 0018     25 LABEL : Cell Value, String Constant - SdHglDCqVV len=0 
' 0018     20 LABEL : Cell Value, String Constant - sGlzs len=0 
' 0018     25 LABEL : Cell Value, String Constant - ubdUpZoNem len=0 
' 0018     22 LABEL : Cell Value, String Constant - VdsgRsX len=0 
' 0018     25 LABEL : Cell Value, String Constant - VnDeDPTuyh len=0 
' 0018     24 LABEL : Cell Value, String Constant - VndoUbfMx len=0 
' 0018     27 LABEL : Cell Value, String Constant - XeqAegpFfeXG len=0 
' 0018     26 LABEL : Cell Value, String Constant - ZpUPtcQyixE 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
' 00f
... (truncated)