Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 ea86e4d3619d34d9…

MALICIOUS

Office (OLE)

36.5 KB Created: 2020-11-27 11:40:00 Authoring application: Microsoft Excel First seen: 2020-12-25
MD5: fea9056fb488bbe62922d76ea7b0b494 SHA-1: 8a16d71137c177749e6cfb68608840af47c90ce8 SHA-256: ea86e4d3619d34d9cc1ef1d551e5f1bc51ae8955cf7bec8757d97bdbc06d1240
140 Risk Score

Malware Insights

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

The file contains Excel 4.0 macros, specifically an Auto_Open defined name, which is a critical finding indicating the potential for automatic execution upon opening. The presence of dangerous formula APIs like RUN further suggests malicious intent. This mechanism is commonly used to download and execute secondary payloads, making it a high-risk artifact.

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) 6806 bytes
SHA-256: 6dfe29a8078d37ae27f5b408ca5cef05511d2b70320f47356c3e833bbe4fea1e
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 -  jVawhFrtJ
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!B182 
' 0018     23 LABEL : Cell Value, String Constant - CQdpctHx len=0 
' 0018     24 LABEL : Cell Value, String Constant - CrkjMJTca len=0 
' 0018     20 LABEL : Cell Value, String Constant - eZdNx len=0 
' 0018     23 LABEL : Cell Value, String Constant - FaPpbGqJ len=0 
' 0018     24 LABEL : Cell Value, String Constant - fBaGxbjpf len=0 
' 0018     25 LABEL : Cell Value, String Constant - FkcwsrsARo len=0 
' 0018     23 LABEL : Cell Value, String Constant - hyAhNUQm len=0 
' 0018     25 LABEL : Cell Value, String Constant - jYQZetUJpD len=0 
' 0018     22 LABEL : Cell Value, String Constant - nFuksoz len=0 
' 0018     20 LABEL : Cell Value, String Constant - nPrvH len=0 
' 0018     26 LABEL : Cell Value, String Constant - RiCPmGqRGIA len=0 
' 0018     25 LABEL : Cell Value, String Constant - rsWZFPOPAl len=0 
' 0018     26 LABEL : Cell Value, String Constant - SWWdbVbJvzp len=0 
' 0018     27 LABEL : Cell Value, String Constant - UEoaWsttAvSD len=0 
' 0018     25 LABEL : Cell Value, String Constant - vAvlMbcZPn len=0 
' 0018     20 LABEL : Cell Value, String Constant - WHewe len=0 
' 0018     21 LABEL : Cell Value, String Constant - WPUvLL len=0 
' 0018     26 LABEL : Cell Value, String Constant - WUOcENCNTij len=0 
' 0018     26 LABEL : Cell Value, String Constant - XQPKQyVfOAs len=0 
' 0018     22 LABEL : Cell Value, String Constant - zhaWbYR 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
' 00
... (truncated)