Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 8a8724abfbf1d23e…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:40:25 Authoring application: Microsoft Excel First seen: 2021-06-13
MD5: 1f3b9fddc7f03b39db6099ee3c64e961 SHA-1: cf3cb9d422a14462d219ddb1f52d57345c2d19a8 SHA-256: 8a8724abfbf1d23ee398acfbd501481a34f16fb160a2a51cfc1898c15ed0041b
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 flagged as critical due to the use of dangerous formula APIs like RUN. This indicates the macro is designed to execute arbitrary code, likely downloading and running a second-stage payload. The presence of the Auto_Open entry and the use of dangerous functions strongly suggest a malicious intent to compromise the user's system.

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) 6431 bytes
SHA-256: e0c0165a3912b1534fc1a31fe68fed77a94d46641adeb5c823d32540b7e02647
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     12 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  iKo
' 0018     23 LABEL : Cell Value, String Constant - aCRRrdMT len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!A184 
' 0018     23 LABEL : Cell Value, String Constant - AyCRnlPk len=0 
' 0018     27 LABEL : Cell Value, String Constant - BUmjoUPXxVoo len=0 
' 0018     22 LABEL : Cell Value, String Constant - EQxEuYz len=0 
' 0018     21 LABEL : Cell Value, String Constant - ffPcPX len=0 
' 0018     20 LABEL : Cell Value, String Constant - gwEgJ len=0 
' 0018     26 LABEL : Cell Value, String Constant - hhVeXnAxWlX len=0 
' 0018     25 LABEL : Cell Value, String Constant - jJfKULPreu len=0 
' 0018     25 LABEL : Cell Value, String Constant - jUGVIoXddI len=0 
' 0018     26 LABEL : Cell Value, String Constant - JzIueWXawKO len=0 
' 0018     21 LABEL : Cell Value, String Constant - KJCyGc len=0 
' 0018     21 LABEL : Cell Value, String Constant - mFOJwc len=0 
' 0018     22 LABEL : Cell Value, String Constant - rSKnCvI len=0 
' 0018     26 LABEL : Cell Value, String Constant - TevfShVGYzC len=0 
' 0018     23 LABEL : Cell Value, String Constant - ubuXmMKM len=0 
' 0018     26 LABEL : Cell Value, String Constant - UVSyJnylJRR len=0 
' 0018     23 LABEL : Cell Value, String Constant - UYPyogip len=0 
' 0018     27 LABEL : Cell Value, String Constant - viEkYKFCgtxM len=0 
' 0018     23 LABEL : Cell Value, String Constant - VzdKLTIx len=0 
' 0018     25 LABEL : Cell Value, String Constant - XkiwjkkdRu 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)

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