Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 af6dd3982a216d66…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:43:03 Authoring application: Microsoft Excel First seen: 2021-09-22
MD5: 7ac60e73db35e71e72dca9442b1b172c SHA-1: 06d2c74d7783a31540534483e93912f7f6147da5 SHA-256: af6dd3982a216d668ade34c076fd2dd08c73e4d2c6c3e2ed9e95d02ff01213a9
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 technique for executing malicious code upon opening the workbook. The presence of dangerous formula APIs like RUN indicates the macro is designed to execute arbitrary commands. While no specific URLs or hashes were extracted, the primary function of this macro is to initiate an exploit chain, likely leading to the download and execution of a secondary 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) 6619 bytes
SHA-256: 541bc74fb6957fd32de0e525840c978eecb4d56e9e3da2671cb3ed9fe526e29c
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 -  UdDVAgIWZf
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!E151 
' 0018     26 LABEL : Cell Value, String Constant - azLOfezHuGr len=0 
' 0018     25 LABEL : Cell Value, String Constant - BBizqudHwt len=0 
' 0018     21 LABEL : Cell Value, String Constant - bdtnug len=0 
' 0018     20 LABEL : Cell Value, String Constant - eDuTy len=0 
' 0018     27 LABEL : Cell Value, String Constant - FOZEshHOiGfc len=0 
' 0018     25 LABEL : Cell Value, String Constant - IhVXlMuGZt len=0 
' 0018     26 LABEL : Cell Value, String Constant - JsDfZOyEARo len=0 
' 0018     20 LABEL : Cell Value, String Constant - KirhU len=0 
' 0018     20 LABEL : Cell Value, String Constant - lwcyA len=0 
' 0018     27 LABEL : Cell Value, String Constant - mdJsEOFOWigY len=0 
' 0018     27 LABEL : Cell Value, String Constant - mlKHOvOcJXAM len=0 
' 0018     22 LABEL : Cell Value, String Constant - npVnozz len=0 
' 0018     25 LABEL : Cell Value, String Constant - PbRtssfSGd len=0 
' 0018     24 LABEL : Cell Value, String Constant - rqADeWUnu len=0 
' 0018     22 LABEL : Cell Value, String Constant - semsrmy len=0 
' 0018     21 LABEL : Cell Value, String Constant - tqsDTw len=0 
' 0018     24 LABEL : Cell Value, String Constant - vxnMddhGr len=0 
' 0018     23 LABEL : Cell Value, String Constant - wajJTBiD len=0 
' 0018     23 LABEL : Cell Value, String Constant - XpNAppYq len=0 
' 0018     26 LABEL : Cell Value, String Constant - ZjEtqLvYmPl 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)

Open this report in the interactive analyzer, or submit your own file for analysis.