Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 579bfa76b3c396d4…

MALICIOUS

Office (OLE)

36.0 KB Created: 2020-11-25 10:25:29 Authoring application: Microsoft Excel First seen: 2021-09-23
MD5: 7442939288d75023c4c74c384f504762 SHA-1: f3a7571dfe0bb47d0b70380c45faaf6eba99c481 SHA-256: 579bfa76b3c396d49229df21169b759a64148d4fd7fd7ef334997bc58e477aef
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 automatic execution. The presence of dangerous formula APIs like RUN further suggests malicious intent. While the exact payload is not discernible from the provided evidence, the mechanism points to an attempt to execute arbitrary code when the document is opened.

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) 6453 bytes
SHA-256: 52fbcb10db13f8e6f626d435004ccde44483b8b3d8d960f58591a4a26e9f3b8b
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0085     14 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  jXXeQ
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!C178 
' 0018     22 LABEL : Cell Value, String Constant - BoDOJos len=0 
' 0018     23 LABEL : Cell Value, String Constant - gBheiVIN len=0 
' 0018     27 LABEL : Cell Value, String Constant - HdYLbssfrZtr len=0 
' 0018     27 LABEL : Cell Value, String Constant - JMAiwYnQpMJo len=0 
' 0018     25 LABEL : Cell Value, String Constant - jUJfHMRZoS len=0 
' 0018     22 LABEL : Cell Value, String Constant - NCcsvFH len=0 
' 0018     23 LABEL : Cell Value, String Constant - oicNaOXL len=0 
' 0018     24 LABEL : Cell Value, String Constant - OoVnmbsOo len=0 
' 0018     26 LABEL : Cell Value, String Constant - PFKuccCVCuq len=0 
' 0018     22 LABEL : Cell Value, String Constant - QchvdAt len=0 
' 0018     22 LABEL : Cell Value, String Constant - qYbfVlg len=0 
' 0018     22 LABEL : Cell Value, String Constant - rfyABdG len=0 
' 0018     21 LABEL : Cell Value, String Constant - rujBjx len=0 
' 0018     26 LABEL : Cell Value, String Constant - stwUrbfAiPB len=0 
' 0018     23 LABEL : Cell Value, String Constant - TpsbdgEU len=0 
' 0018     25 LABEL : Cell Value, String Constant - UvWxRglpkK len=0 
' 0018     21 LABEL : Cell Value, String Constant - vICbGe len=0 
' 0018     25 LABEL : Cell Value, String Constant - ypgVjywKzy len=0 
' 0018     23 LABEL : Cell Value, String Constant - zCmnKxuL len=0 
' 0018     20 LABEL : Cell Value, String Constant - ZiiCN 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     1
... (truncated)

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