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

Static analysis result for SHA-256 079e55bbaaf6e8b6…

MALICIOUS

Office (OLE) / .XLS

380.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel
MD5: f7c9fecdda22f4b61733db46c98cb131 SHA-1: 4cf34f81deb5bf3c352587c3feea13837dcfb4d3 SHA-256: 079e55bbaaf6e8b6286628ed6801e81e7bb753747c71cde1cb164797f2125792
102 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.005 Visual Basic T1105 Ingress Tool Transfer

The sample is an Excel 4.0 (XLM) macro-enabled spreadsheet that contains an Auto_Open macro. The macro attempts to lure the user into enabling content, which then proceeds to download and execute a second-stage payload from one of the two provided URLs. The reconstructed URL is "https://caiogabriel.com.br/tOKLlSLW/lena.html" and "https://bwctradex.com/BcotoLXTr1y/lena.html". The macro also attempts to use rundll32.exe and regsvr32.exe for execution.

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