Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 d235443ff87bae0d…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-27 11:45:50 Authoring application: Microsoft Excel First seen: 2021-10-14
MD5: e50f3fedf75cf2c7bad64bac64ebb0f5 SHA-1: a7cd940d283090b301c50fcfbb080aa1803037f0 SHA-256: d235443ff87bae0d66b7899b400596926665baf86fcb9feb01fc0bead39c05fc
140 Risk Score

Malware Insights

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

The file is an Excel 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, specifically 'RUN'. This strongly suggests the macro is designed to execute arbitrary code or download a second-stage payload upon opening the document. No specific family could be identified, and no direct IOCs like URLs or hashes were extracted from the macro content.

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) 6829 bytes
SHA-256: c7b1918f6d4436bec5d32bf4418cad55ddf45d39bbc4d8f3a8c5ce1efdd6406c
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     19 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  hsGHadCsKs
' 0018     22 LABEL : Cell Value, String Constant - aCDyBkP len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!A141 
' 0018     25 LABEL : Cell Value, String Constant - cIgzpjnvoi len=0 
' 0018     23 LABEL : Cell Value, String Constant - DFLZqyHL len=0 
' 0018     23 LABEL : Cell Value, String Constant - eQzBwlXZ len=0 
' 0018     26 LABEL : Cell Value, String Constant - fUZfETgPYdY len=0 
' 0018     25 LABEL : Cell Value, String Constant - gsxsbbdvRc len=0 
' 0018     27 LABEL : Cell Value, String Constant - hYpVQEESUnqw len=0 
' 0018     27 LABEL : Cell Value, String Constant - JkZkEuRiClhK len=0 
' 0018     22 LABEL : Cell Value, String Constant - MskjIgq len=0 
' 0018     23 LABEL : Cell Value, String Constant - NkJIBUrk len=0 
' 0018     22 LABEL : Cell Value, String Constant - oDGnuPl len=0 
' 0018     23 LABEL : Cell Value, String Constant - OFuVMJpq len=0 
' 0018     22 LABEL : Cell Value, String Constant - OILbWQv len=0 
' 0018     22 LABEL : Cell Value, String Constant - oYTGMHF len=0 
' 0018     21 LABEL : Cell Value, String Constant - QGBtHb len=0 
' 0018     21 LABEL : Cell Value, String Constant - USiMKB len=0 
' 0018     27 LABEL : Cell Value, String Constant - whoQPVfZzImE len=0 
' 0018     22 LABEL : Cell Value, String Constant - wtFCniN len=0 
' 0018     25 LABEL : Cell Value, String Constant - xNVWaBvzxK len=0 
' 0018     21 LABEL : Cell Value, String Constant - ZCZZnz 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.