Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 0a71be2617172aed…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:44:11 Authoring application: Microsoft Excel First seen: 2021-10-14
MD5: 8c5a15f88a009663ebc6056d78d2a7d6 SHA-1: 6f3d23984fc96f68c16488c318198965cce213b4 SHA-256: 0a71be2617172aed61a3eb82b4c3d597f8b0c15fcbacc76e60f5d576198a2073
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 macro, which is a known method for executing malicious code upon opening the document. The presence of dangerous formula APIs in the Auto_Open macro indicates an intent to run arbitrary commands. While the specific payload is not directly visible, the setup strongly suggests it's designed to download and execute a second-stage malicious file.

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) 6425 bytes
SHA-256: 55ec93d96c7371e82e841b7bdde73abd0ff4b340253dca4fdcc98f24e038a33e
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 -  Fvlt
' 0018     23 LABEL : Cell Value, String Constant - aMSDKmWh len=0 
' 0018     23 LABEL : Cell Value, String Constant - aTdoYieU len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!A134 
' 0018     26 LABEL : Cell Value, String Constant - dftnXSmSKlb len=0 
' 0018     26 LABEL : Cell Value, String Constant - DxeSIzAOzLg len=0 
' 0018     23 LABEL : Cell Value, String Constant - EglCxYuU len=0 
' 0018     20 LABEL : Cell Value, String Constant - GNSDW len=0 
' 0018     25 LABEL : Cell Value, String Constant - hWQMqxlqHw len=0 
' 0018     22 LABEL : Cell Value, String Constant - IJjFmpK len=0 
' 0018     21 LABEL : Cell Value, String Constant - kVJZtN len=0 
' 0018     27 LABEL : Cell Value, String Constant - llUylWsrLMct len=0 
' 0018     20 LABEL : Cell Value, String Constant - lxLjm len=0 
' 0018     25 LABEL : Cell Value, String Constant - mFqnsxMbik len=0 
' 0018     23 LABEL : Cell Value, String Constant - MPyeyWOM len=0 
' 0018     23 LABEL : Cell Value, String Constant - oQpZavhT len=0 
' 0018     26 LABEL : Cell Value, String Constant - qLcyXUHKVtt len=0 
' 0018     27 LABEL : Cell Value, String Constant - rDxymuANLIIm len=0 
' 0018     22 LABEL : Cell Value, String Constant - RWJSOss len=0 
' 0018     24 LABEL : Cell Value, String Constant - SaIngvIyj len=0 
' 0018     24 LABEL : Cell Value, String Constant - SirSqblSY len=0 
' 0018     24 LABEL : Cell Value, String Constant - YtTOETYaL 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.