Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 e4241398eab96895…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:39:53 Authoring application: Microsoft Excel First seen: 2021-07-10
MD5: af4c54b98a1b9049c00901070cd49354 SHA-1: 504f73e1009ff1f49ce5caa0a8f1f6620aba9241 SHA-256: e4241398eab9689597c1ea4bc7360e8b6bc62b01a2647263e3030c37b98a4bba
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 macros, specifically an Auto_Open macro. This macro is designed to execute automatically when the workbook is opened, indicating an attempt to run arbitrary code. The presence of dangerous formula APIs within the macro further increases the risk. The exact payload or further actions are not discernible from the provided evidence, leading to an unknown family classification.

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) 6647 bytes
SHA-256: cd5da7cd6dd8696837d924de5a5c9d242df599de7d9c5e6620bc691d02d638ac
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 -  rWQetvdbSo
' 0018     22 LABEL : Cell Value, String Constant - AkCGgfA len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!D195 
' 0018     26 LABEL : Cell Value, String Constant - hEUETgEpMhM len=0 
' 0018     22 LABEL : Cell Value, String Constant - HwYPfNo len=0 
' 0018     21 LABEL : Cell Value, String Constant - hXZogT len=0 
' 0018     25 LABEL : Cell Value, String Constant - iqUjRMftuE len=0 
' 0018     25 LABEL : Cell Value, String Constant - iRCNmPSAqw len=0 
' 0018     22 LABEL : Cell Value, String Constant - ItSPHoq len=0 
' 0018     23 LABEL : Cell Value, String Constant - lwupYTBD len=0 
' 0018     20 LABEL : Cell Value, String Constant - mkxEW len=0 
' 0018     25 LABEL : Cell Value, String Constant - MniJyTTVPG len=0 
' 0018     26 LABEL : Cell Value, String Constant - nAqgoOSaOyS len=0 
' 0018     26 LABEL : Cell Value, String Constant - nbdtkLISSXs len=0 
' 0018     26 LABEL : Cell Value, String Constant - PCsEIGxqqsI len=0 
' 0018     25 LABEL : Cell Value, String Constant - SUGmmsHYnS len=0 
' 0018     25 LABEL : Cell Value, String Constant - uUUjcIFeyB len=0 
' 0018     22 LABEL : Cell Value, String Constant - VFceeOq len=0 
' 0018     21 LABEL : Cell Value, String Constant - VzpWqf len=0 
' 0018     26 LABEL : Cell Value, String Constant - XygbTcALpSo len=0 
' 0018     25 LABEL : Cell Value, String Constant - YncpnXHJqO len=0 
' 0018     24 LABEL : Cell Value, String Constant - yTqXFVCqU 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)