Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 321775c9fdee5386…

MALICIOUS

Office (OLE)

236.0 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel First seen: 2020-09-07
MD5: 0600cf3e14534e980496a5b4888a4d78 SHA-1: c62e5b498b1f10d675fb0be9b677e369a9b6012b SHA-256: 321775c9fdee53868d0d48af534373674f586848da52a73b38f42216e91f1248
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 Excel 4.0 macros, indicated by multiple critical heuristic firings including OLE_XLM_AUTOOPEN and OLE_XLM_DANGEROUS_FN. The document body presents a lure to enable editing and content, which would trigger the embedded Auto_Open macro. This macro is designed to execute dangerous functions, likely for initial execution of a malicious 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) 326247 bytes
SHA-256: 54a4e4119a518a6c9c16655aca71f67cd5f153fbaa64cd70868fcc62239a26fd
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     17 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  wFHcM7kl
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open hidden len=7 ptgNameX  NAMEIDX 2 
' 0018     31 LABEL : Cell Value, String Constant -           hidden len=7 ptgRef3d  Sheet!HC2057 
' 0018     26 LABEL : Cell Value, String Constant - faFIRiqfoZw len=0 
' 0018     27 LABEL : Cell Value, String Constant - gClpgqTFyDJR len=0 
' 0018     27 LABEL : Cell Value, String Constant - HKWNFYMipOhi len=0 
' 0018     23 LABEL : Cell Value, String Constant - NojiMgjR len=0 
' 0018     26 LABEL : Cell Value, String Constant - nxxWlgtDahD len=0 
' 0018     27 LABEL : Cell Value, String Constant - SLGeWKgiiryU len=0 
' 0018     25 LABEL : Cell Value, String Constant - vDDsGkLJEa len=0 
' 0018     25 LABEL : Cell Value, String Constant - veDRSxBrQN len=0 
' 0018     27 LABEL : Cell Value, String Constant - WiNXQNOyXRlP len=0 
' 0018     26 LABEL : Cell Value, String Constant - wwwfQQrcoxs len=0 
' 0018     26 LABEL : Cell Value, String Constant - XByvckhpHcn len=0 
' 0018     26 LABEL : Cell Value, String Constant - XJYtNpVeKgv len=0 
' 0018     27 LABEL : Cell Value, String Constant - YFMWLvRFQRXq len=0 
' 0018     21 LABEL : Cell Value, String Constant - YnDaDI len=0 
' 0018     25 LABEL : Cell Value, String Constant - zZRTTBENOH 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, Str
... (truncated)