Malicious Office (OLE) / .XLS — malware analysis report

Static analysis result for SHA-256 64357e0ac66ee1aa…

MALICIOUS

Office (OLE) / .XLS

380.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel
MD5: 09617ed1342faf7b10c8050de223ec41 SHA-1: 61bbbc77635a5b9f5971e43bdd1fd3f049d7189e SHA-256: 64357e0ac66ee1aa638b3467e8f6435d24a1771319edc7c87257e80cd9163c65
102 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.005 Visual Basic T1204.002 Malicious File

The sample is an Excel 4.0 macro-enabled spreadsheet that uses an Auto_Open macro to execute. The macro attempts to download a payload from one of two URLs: https://caiogabriel.com.br/tOKLlSLW/lena.html or https://bwctradex.com/BcotoLXTr1y/lena.html. The macro also contains commands to execute rundll32.exe and regsvr32.exe, indicating it is designed to download and run a second-stage 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.
  • 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.
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://caiogabriel.com.br/tOKLlSLW/lena.html
    • https://bwctradex.com/BcotoLXTr1y/lena.html

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
d46ad6b52df62d280ddc3eb28f4fdfc78bc84dc99077b9aa50809affc4be6057
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8812 bytes