Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 8dfe1980dac89748…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:39:33 Authoring application: Microsoft Excel First seen: 2021-06-20
MD5: 91e77c4415740adcf41554809dabe917 SHA-1: 73aeec924d930b7512755be899ae7d6ee9fc4108 SHA-256: 8dfe1980dac89748f0042999cbb986da881e84c6bd266cba39503a98af0c2179
140 Risk Score

Malware Insights

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

The file is an Excel macro-enabled document containing Excel 4.0 (XLM) macros. The critical heuristics indicate the presence of an Auto_Open defined name and the use of dangerous formula APIs, suggesting an attempt to automatically execute code upon opening. No specific IOCs like URLs or hashes were extracted, but the technique strongly implies the execution of a malicious 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) 6508 bytes
SHA-256: 0a1aa1a68316293050eba1cf5dbb3027d6faa1df3d5561b1ffd141c007db517b
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 -  RcOVBPx
' 0018     26 LABEL : Cell Value, String Constant - AIkJfJDMQEI len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!F133 
' 0018     21 LABEL : Cell Value, String Constant - avxtrY len=0 
' 0018     24 LABEL : Cell Value, String Constant - BxOmUCFbz len=0 
' 0018     27 LABEL : Cell Value, String Constant - cPPdNsxOpCUN len=0 
' 0018     25 LABEL : Cell Value, String Constant - IxjcOXNVRJ len=0 
' 0018     26 LABEL : Cell Value, String Constant - IYlHhhvAbsT len=0 
' 0018     21 LABEL : Cell Value, String Constant - JZUudt len=0 
' 0018     24 LABEL : Cell Value, String Constant - kKQnnpJbj len=0 
' 0018     20 LABEL : Cell Value, String Constant - mluZj len=0 
' 0018     27 LABEL : Cell Value, String Constant - NVmwpUdqnlGu len=0 
' 0018     24 LABEL : Cell Value, String Constant - pquogjhJW len=0 
' 0018     23 LABEL : Cell Value, String Constant - QcctENPM len=0 
' 0018     25 LABEL : Cell Value, String Constant - tZjUfKbysz len=0 
' 0018     27 LABEL : Cell Value, String Constant - uMnMVramCuUA len=0 
' 0018     21 LABEL : Cell Value, String Constant - Vazcnj len=0 
' 0018     24 LABEL : Cell Value, String Constant - VlwyGxzYM len=0 
' 0018     26 LABEL : Cell Value, String Constant - WdLDqcwGlwy len=0 
' 0018     24 LABEL : Cell Value, String Constant - wMyZMIazK len=0 
' 0018     20 LABEL : Cell Value, String Constant - zEYND len=0 
' 0018     22 LABEL : Cell Value, String Constant - ZZCGIMG 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
' 
... (truncated)

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