Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 a048aafd2802cb82…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-27 11:41:35 Authoring application: Microsoft Excel First seen: 2021-05-26
MD5: 69bc5d9151a379a859c2b3841093fb5f SHA-1: cf17ef78214164275af656bc4d50766a0069a9bf SHA-256: a048aafd2802cb821848086c75a448b245c63abec974076c0a20d077142f7bb3
140 Risk Score

Malware Insights

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

The sample is an Excel file containing Excel 4.0 (XLM) macros, specifically an Auto_Open macro. This indicates an attempt to execute arbitrary code upon opening the document. The presence of dangerous formula APIs further supports this, suggesting the macro is designed to download and execute a second-stage 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) 6626 bytes
SHA-256: f416ee2a0d865d4cf8a014caafe10574f62ac17ccd532910171a2005cc8bddf8
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     13 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  rRNW
' 0018     22 LABEL : Cell Value, String Constant - AjVEqjz len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!H188 
' 0018     24 LABEL : Cell Value, String Constant - CZMqdcUKB len=0 
' 0018     21 LABEL : Cell Value, String Constant - DeeCPv len=0 
' 0018     25 LABEL : Cell Value, String Constant - DkWpFCTHCy len=0 
' 0018     25 LABEL : Cell Value, String Constant - eILHHYdaBx len=0 
' 0018     23 LABEL : Cell Value, String Constant - FvkqaOdJ len=0 
' 0018     25 LABEL : Cell Value, String Constant - hMsmUawvns len=0 
' 0018     25 LABEL : Cell Value, String Constant - IiKqzUipQS len=0 
' 0018     27 LABEL : Cell Value, String Constant - JdhkKvjLvXoY len=0 
' 0018     25 LABEL : Cell Value, String Constant - KdlAHLMWqV len=0 
' 0018     22 LABEL : Cell Value, String Constant - mtphOZK len=0 
' 0018     26 LABEL : Cell Value, String Constant - MVmqKPSIWQN len=0 
' 0018     23 LABEL : Cell Value, String Constant - oXJSLAtO len=0 
' 0018     23 LABEL : Cell Value, String Constant - QOCeZnSf len=0 
' 0018     27 LABEL : Cell Value, String Constant - QoEliBgZnpnD len=0 
' 0018     20 LABEL : Cell Value, String Constant - vRXEg len=0 
' 0018     27 LABEL : Cell Value, String Constant - womNHXLbBlHd len=0 
' 0018     24 LABEL : Cell Value, String Constant - xDfhNIyzv len=0 
' 0018     21 LABEL : Cell Value, String Constant - yjbvpQ len=0 
' 0018     25 LABEL : Cell Value, String Constant - zqHmyWcoyr 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.