Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 ac7da8e9dada0cd7…

MALICIOUS

Office (OLE)

250.5 KB Created: 2020-08-05 09:00:36 Authoring application: Microsoft Excel First seen: 2020-09-07
MD5: 96b14a6c053807e0230e30e553f2b876 SHA-1: d1a2505e271cc6f91c56aa9e60a7ffae998185a9 SHA-256: ac7da8e9dada0cd7e7682457664b8b086f6fc438d254e4db2d3346fc7e2f5c98
180 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.005 Visual Basic T1203 Exploitation for Client Execution

The sample is an Excel 4.0 macro-enabled workbook. Heuristics indicate the presence of an Auto_Open macro, which is designed to execute automatically when the workbook is opened. The document body contains a social engineering lure to 'Enable Editing' and 'Enable Content', suggesting the user is expected to bypass security warnings to trigger the macro. The macro uses dangerous formula APIs and includes environment evasion techniques, indicating malicious intent to execute a payload.

Heuristics 4

  • 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.
  • XLM Auto_Open environment-evasion HALT gate high OLE_XLM_ENVIRONMENT_EVASION_HALT
    Excel 4.0 macro sheet auto-executes multiple GET.WORKSPACE / GET.WINDOW environment checks and halts execution when the host does not match the expected user environment. This is a common sandbox-evasion pattern in XLM malware and is stronger than a bare XLM macro-sheet indicator.
  • 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) 271139 bytes
SHA-256: 035ce7836e9322217c574bc5de898a95a27e25f59d86defb892a99ba260b4c2b
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 -  s9rT
' 0018     26 LABEL : Cell Value, String Constant - auTNnbFiTCc len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open hidden len=7 ptgNameX  NAMEIDX 15 
' 0018     27 LABEL : Cell Value, String Constant - bbghlLDcBtHo len=0 
' 0018     27 LABEL : Cell Value, String Constant - CMwihoXmLvcv len=0 
' 0018     25 LABEL : Cell Value, String Constant - dLzoKHniYS len=0 
' 0018     27 LABEL : Cell Value, String Constant - glQZaaGNNbdQ len=0 
' 0018     23 LABEL : Cell Value, String Constant - KgVliPoY len=0 
' 0018     24 LABEL : Cell Value, String Constant - kspbHOdyv len=0 
' 0018     24 LABEL : Cell Value, String Constant - MzpvGBSkR len=0 
' 0018     25 LABEL : Cell Value, String Constant - nCridzRDuP len=0 
' 0018     21 LABEL : Cell Value, String Constant - sylLEL len=0 
' 0018     22 LABEL : Cell Value, String Constant - tBpiVnM len=0 
' 0018     24 LABEL : Cell Value, String Constant - TSsGCTUKX len=0 
' 0018     23 LABEL : Cell Value, String Constant - VnNakKGM len=0 
' 0018     31 LABEL : Cell Value, String Constant -           hidden len=7 ptgRef3d  Sheet!CO12412 
' 0018     23 LABEL : Cell Value, String Constant - XBhlziwG len=0 
' 0018     23 LABEL : Cell Value, String Constant - XwTUgrKP 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     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
' 00
... (truncated)