Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 84b93f87990539a0…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:38:15 Authoring application: Microsoft Excel First seen: 2021-10-02
MD5: 9c9e391ab194416d27acb7d4c73c5022 SHA-1: 01f29b795f692210cdc245e8b183709410b66c69 SHA-256: 84b93f87990539a0f9374ec487ea940b1e90fa9f135ff739d8effb0f3b44e579
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 function, which is a known method for executing malicious code. The heuristics indicate the use of dangerous formula APIs within the macro, suggesting it's designed to run arbitrary commands. The macro likely acts as a downloader for a secondary payload, though the specific URL or payload is not directly extractable from the provided evidence.

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) 6423 bytes
SHA-256: 499c2aab8f8608a0f2b1b58a8bcdb5c2f907ef185ea3b6af18721daeb315413f
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     15 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  OALBtK
' 0018     22 LABEL : Cell Value, String Constant - abmajjN len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!B176 
' 0018     23 LABEL : Cell Value, String Constant - dNEqHkpw len=0 
' 0018     21 LABEL : Cell Value, String Constant - eiLAHG len=0 
' 0018     27 LABEL : Cell Value, String Constant - GAHCsllWGWSn len=0 
' 0018     23 LABEL : Cell Value, String Constant - HAXIwfBP len=0 
' 0018     24 LABEL : Cell Value, String Constant - ijHHeSgli len=0 
' 0018     27 LABEL : Cell Value, String Constant - iYpYiErtJfuK len=0 
' 0018     21 LABEL : Cell Value, String Constant - kGgkfq len=0 
' 0018     20 LABEL : Cell Value, String Constant - lkEIO len=0 
' 0018     26 LABEL : Cell Value, String Constant - nBouAYKfJLE len=0 
' 0018     24 LABEL : Cell Value, String Constant - oOAvtpLdv len=0 
' 0018     22 LABEL : Cell Value, String Constant - qczAIab len=0 
' 0018     21 LABEL : Cell Value, String Constant - rVDOpW len=0 
' 0018     20 LABEL : Cell Value, String Constant - tnRDO len=0 
' 0018     20 LABEL : Cell Value, String Constant - trRlH len=0 
' 0018     21 LABEL : Cell Value, String Constant - wAsEOg len=0 
' 0018     21 LABEL : Cell Value, String Constant - WlngwA len=0 
' 0018     21 LABEL : Cell Value, String Constant - wSPiWY len=0 
' 0018     25 LABEL : Cell Value, String Constant - ZHOXDUjazK len=0 
' 0018     22 LABEL : Cell Value, String Constant - zjKlbKp 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 LABELSST : Cell
... (truncated)

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