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

Static analysis result for SHA-256 c4af89aaed34b23e…

MALICIOUS

Office (OLE) / .XLS

380.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel
MD5: f3f7828e5bcffbff315dbff248ed8664 SHA-1: ea973d1af20cd9277c3c2f8603184007e2e85d6c SHA-256: c4af89aaed34b23e460de02a0188ed50a179cff35c05578e41bd6e6b0407c33e
102 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File

The file is an Excel 4.0 macro-enabled spreadsheet that contains an Auto_Open defined name, indicating it will execute macros automatically upon opening. The presence of an 'enable lure' heuristic suggests the document attempts to trick the user into enabling macros. The embedded URLs likely host the second-stage payload. The XLM macros are the primary mechanism 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 — context-specific rules above attribute URLs they actually evaluated; this rule lists URLs that were present in the bytes but were not otherwise tied to a specific finding.
    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