Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 b032c4116a0786a6…

MALICIOUS

Office (OLE)

36.5 KB Created: 2020-11-27 11:42:15 Authoring application: Microsoft Excel First seen: 2021-10-01
MD5: 870c4710bc14df5e85521521f614e9f4 SHA-1: 90f6cdc007b460705f19469c69dd9a20d0c8817f SHA-256: b032c4116a0786a652fe614ae90c80407c7e5407bdf0c20d9aecd8bda2060b68
140 Risk Score

Malware Insights

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

This Excel file contains Excel 4.0 macros, specifically an Auto_Open defined name, which is a known technique for executing malicious code upon opening the workbook. The critical heuristic firings indicate the presence of dangerous formula APIs, suggesting the macro is designed to run arbitrary commands or download further payloads. The macro sheet itself is heavily obfuscated with junk data, making specific payload analysis impossible from static inspection.

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) 6807 bytes
SHA-256: 4ef2a82eef67cd050a7a905948de017bbe14ac3eab76a133f64c3ecc8bdcb91f
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 -  YpERqzbyJS
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!E136 
' 0018     21 LABEL : Cell Value, String Constant - BwEiyx len=0 
' 0018     25 LABEL : Cell Value, String Constant - cdapxywLut len=0 
' 0018     22 LABEL : Cell Value, String Constant - eGLRJKL len=0 
' 0018     21 LABEL : Cell Value, String Constant - FsudlJ len=0 
' 0018     25 LABEL : Cell Value, String Constant - FyrHMVyDUM len=0 
' 0018     22 LABEL : Cell Value, String Constant - ImgxPBa len=0 
' 0018     27 LABEL : Cell Value, String Constant - imyuhfMXFsHI len=0 
' 0018     25 LABEL : Cell Value, String Constant - iwBHiqQUxn len=0 
' 0018     27 LABEL : Cell Value, String Constant - mMVuOymNXCuD len=0 
' 0018     22 LABEL : Cell Value, String Constant - OAFAZgr len=0 
' 0018     21 LABEL : Cell Value, String Constant - pRXsyQ len=0 
' 0018     20 LABEL : Cell Value, String Constant - Qboew len=0 
' 0018     22 LABEL : Cell Value, String Constant - QNErUVo len=0 
' 0018     26 LABEL : Cell Value, String Constant - QvpFYkshkQv len=0 
' 0018     20 LABEL : Cell Value, String Constant - Ryspt len=0 
' 0018     25 LABEL : Cell Value, String Constant - uzPHDRodfu len=0 
' 0018     22 LABEL : Cell Value, String Constant - voGgmTd len=0 
' 0018     27 LABEL : Cell Value, String Constant - wyJLbukOyrdY len=0 
' 0018     24 LABEL : Cell Value, String Constant - XNCmvZTKj len=0 
' 0018     25 LABEL : Cell Value, String Constant - yGpzYurNZf 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.