Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 7fa23b1dcdf73a60…

MALICIOUS

Office (OLE)

253.0 KB Created: 2020-08-10 13:38:54 Authoring application: Microsoft Excel First seen: 2020-09-07
MD5: a1921c5eaa421e2572758d39543daf0a SHA-1: d772895781a3f8510be899868c25e9f6d7df0e0c SHA-256: 7fa23b1dcdf73a60df190003d1297f0a66c0db99ba4f77aefab83fb2cac31252
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 file containing a malicious Excel 4.0 macro sheet with an Auto_Open entry. The document body prompts the user to "Enable Editing" and "Enable Content", a common lure for macro execution. The XLM macro uses dangerous functions and includes environment evasion techniques, indicating it is designed to execute a payload. No specific family could be identified.

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) 274149 bytes
SHA-256: a348b47ca703e3f5485cfe7ba7f656527ff9486adbcc14838b6122b74ee38c6d
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     18 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  G7SLOQqp2
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open hidden len=7 ptgNameX  NAMEIDX 6 
' 0018     21 LABEL : Cell Value, String Constant - CHYuDu len=0 
' 0018     25 LABEL : Cell Value, String Constant - cyHwTAJgFq len=0 
' 0018     24 LABEL : Cell Value, String Constant - HpHFLCoaE len=0 
' 0018     25 LABEL : Cell Value, String Constant - hPqSdXOrlP len=0 
' 0018     27 LABEL : Cell Value, String Constant -       hidden len=7 ptgRef3d  Sheet!DZ1649 
' 0018     20 LABEL : Cell Value, String Constant - kTyEg len=0 
' 0018     27 LABEL : Cell Value, String Constant - llpWhaVQmamF len=0 
' 0018     24 LABEL : Cell Value, String Constant - MysfevHzn len=0 
' 0018     26 LABEL : Cell Value, String Constant - PiwYMGBLPyv len=0 
' 0018     24 LABEL : Cell Value, String Constant - qiXGdWuXi len=0 
' 0018     21 LABEL : Cell Value, String Constant - rgMyiT len=0 
' 0018     21 LABEL : Cell Value, String Constant - tKhknW len=0 
' 0018     26 LABEL : Cell Value, String Constant - UEZKPrGlDCO len=0 
' 0018     27 LABEL : Cell Value, String Constant - wAIJkXVoGShH len=0 
' 0018     26 LABEL : Cell Value, String Constant - wAToJEJnWXN len=0 
' 0018     27 LABEL : Cell Value, String Constant - YbORqbqpEAnz 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
' 00f
... (truncated)