Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 d34f7ecf33ee8e60…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-27 11:37:41 Authoring application: Microsoft Excel First seen: 2020-12-25
MD5: 06af8fb54394eea88ccf94e672064588 SHA-1: 7da1b9a2e49e84634d1ffec76b9d17ce8c17977b SHA-256: d34f7ecf33ee8e6010e4a86deaa87abd62774028aeccc550f45ffd0484544b9c
140 Risk Score

Malware Insights

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

The critical heuristics indicate the presence of an Excel 4.0 macro sheet with an Auto_Open entry, which is a common technique for executing malicious code upon opening the document. The macro sheet contains dangerous formula APIs, suggesting it's designed to run arbitrary commands. No specific IOCs like URLs or hashes were extracted, but the technique itself is highly suspicious.

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) 6712 bytes
SHA-256: 37c149b1c8b306ac638ad0043580bf9644839a2ea9f4f9b8dcfb540f0fc0b414
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     16 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  pfzXYgc
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!H194 
' 0018     23 LABEL : Cell Value, String Constant - BsHfdUIP len=0 
' 0018     20 LABEL : Cell Value, String Constant - BVbmH len=0 
' 0018     26 LABEL : Cell Value, String Constant - cdBvaPmpGLA len=0 
' 0018     20 LABEL : Cell Value, String Constant - dppZb len=0 
' 0018     27 LABEL : Cell Value, String Constant - EoAhmJHwSkEA len=0 
' 0018     27 LABEL : Cell Value, String Constant - EPQUcwXleagy len=0 
' 0018     27 LABEL : Cell Value, String Constant - fUfoJmqQlpMF len=0 
' 0018     27 LABEL : Cell Value, String Constant - Ghcvtarhjcig len=0 
' 0018     23 LABEL : Cell Value, String Constant - hXErACBy len=0 
' 0018     23 LABEL : Cell Value, String Constant - jmenQeaS len=0 
' 0018     23 LABEL : Cell Value, String Constant - mjDZhcNg len=0 
' 0018     24 LABEL : Cell Value, String Constant - nWFxJLMEB len=0 
' 0018     25 LABEL : Cell Value, String Constant - oOIzWcruNS len=0 
' 0018     20 LABEL : Cell Value, String Constant - PoTbg len=0 
' 0018     21 LABEL : Cell Value, String Constant - qZYzKy len=0 
' 0018     21 LABEL : Cell Value, String Constant - sFNykG len=0 
' 0018     25 LABEL : Cell Value, String Constant - TpagaFaJaO len=0 
' 0018     21 LABEL : Cell Value, String Constant - UvcdNX len=0 
' 0018     21 LABEL : Cell Value, String Constant - VhzObN len=0 
' 0018     20 LABEL : Cell Value, String Constant - yNYJB 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 L
... (truncated)

Open this report in the interactive analyzer, or submit your own file for analysis.