Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 73d162f6beba55b4…

MALICIOUS

Office (OLE)

229.5 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel First seen: 2021-07-02
MD5: c14f731800cb83fe9e5403b0b95c4b9a SHA-1: 818d7027fbc8fdec2af4fb4a68e57e7fdcc570f4 SHA-256: 73d162f6beba55b40009c83ff83aa8a88aba846b97f0e9462be1f9a7534040f0
180 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment

The sample is an Excel 4.0 macro-enabled workbook containing an Auto_Open macro. The document body claims the file is encrypted and requires enabling content, a common lure for malicious documents. The XLM macro uses dangerous functions like RUN, indicating it likely downloads and executes a second-stage payload. The presence of an Auto_Open macro suggests it was likely delivered as a spearphishing attachment.

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) 323921 bytes
SHA-256: 7d64b0732a22f77f7e164fcf89b52c6d29ae2eedf737de614d1d48e7ce9955aa
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     16 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  x5kq6qy
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open hidden len=7 ptgNameX  NAMEIDX 10 
' 0018     23 LABEL : Cell Value, String Constant - BkfPhldn len=0 
' 0018     25 LABEL : Cell Value, String Constant - BpMhzoLtvh len=0 
' 0018     24 LABEL : Cell Value, String Constant - DNGGrxPtt len=0 
' 0018     24 LABEL : Cell Value, String Constant - EHBZcDhoF len=0 
' 0018     26 LABEL : Cell Value, String Constant - gFCADbTOwKU len=0 
' 0018     21 LABEL : Cell Value, String Constant - ghoNVW len=0 
' 0018     20 LABEL : Cell Value, String Constant - gSlhH len=0 
' 0018     27 LABEL : Cell Value, String Constant - OPmOHyaBMDZM len=0 
' 0018     31 LABEL : Cell Value, String Constant -           hidden len=7 ptgRef3d  Sheet!BU3287 
' 0018     21 LABEL : Cell Value, String Constant - pTZXGN len=0 
' 0018     25 LABEL : Cell Value, String Constant - RuPEYTwvMw len=0 
' 0018     21 LABEL : Cell Value, String Constant - rWRVvQ len=0 
' 0018     25 LABEL : Cell Value, String Constant - tcCRXxQHAm len=0 
' 0018     20 LABEL : Cell Value, String Constant - tQeQp len=0 
' 0018     27 LABEL : Cell Value, String Constant - ugcamotSHrAQ len=0 
' 0018     20 LABEL : Cell Value, String Constant - ZyyfO 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
' 00fd     10 LAB
... (truncated)