Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 441080d4717225ed…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:36:40 Authoring application: Microsoft Excel First seen: 2021-05-22
MD5: 423817b42225df1129b86bdf13e982fe SHA-1: d497d181e95e3b60a162f9577161e0442d36e7af SHA-256: 441080d4717225ed4e0271cceac62472edb8dd04c046b579478c6fd37a8a42e7
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution

The critical heuristics indicate the presence of Excel 4.0 macros with an Auto_Open function, which is a known method for executing malicious code. The macro sheet contains a reference to a dangerous function, likely used to download and execute a payload. The document body is heavily obfuscated and does not provide clear user-facing content, further suggesting a malicious intent.

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) 6684 bytes
SHA-256: d858f6e575f3d2e32d5eba9e7ea606eb580f3a772a7f8c0e5952364704f9ac4a
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 -  ApsLTOJVQz
' 0018     25 LABEL : Cell Value, String Constant - aHUxddtZkQ len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!A171 
' 0018     22 LABEL : Cell Value, String Constant - CYcLxZP len=0 
' 0018     26 LABEL : Cell Value, String Constant - GGpjNLYPjnw len=0 
' 0018     20 LABEL : Cell Value, String Constant - HUoOR len=0 
' 0018     25 LABEL : Cell Value, String Constant - KdwkvEKndI len=0 
' 0018     20 LABEL : Cell Value, String Constant - LnfVD len=0 
' 0018     26 LABEL : Cell Value, String Constant - MKbXLnsTgIh len=0 
' 0018     23 LABEL : Cell Value, String Constant - MNtkvTrg len=0 
' 0018     25 LABEL : Cell Value, String Constant - mWCDvpWJuV len=0 
' 0018     23 LABEL : Cell Value, String Constant - OiLcICDR len=0 
' 0018     21 LABEL : Cell Value, String Constant - OKuPwr len=0 
' 0018     21 LABEL : Cell Value, String Constant - pNlhar len=0 
' 0018     23 LABEL : Cell Value, String Constant - PSEAJypo len=0 
' 0018     20 LABEL : Cell Value, String Constant - RGXJX len=0 
' 0018     25 LABEL : Cell Value, String Constant - rXbmNDOGjP len=0 
' 0018     24 LABEL : Cell Value, String Constant - sOumpNLWF len=0 
' 0018     26 LABEL : Cell Value, String Constant - TxjwqILPYVd len=0 
' 0018     25 LABEL : Cell Value, String Constant - vcxtvlRJRS len=0 
' 0018     25 LABEL : Cell Value, String Constant - VHvqjnXBGq len=0 
' 0018     24 LABEL : Cell Value, String Constant - wjrgHgTgt 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 
... (truncated)

Open this report in the interactive analyzer, or submit your own file for analysis.