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

Static analysis result for SHA-256 ef4a36a88847d446…

MALICIOUS

Office (OLE) / .XLS

367.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: e5db5eb450d201e974519ec26425c957 SHA-1: f51e72ab3e26a3b82343fdecf5533298a7289e6a SHA-256: ef4a36a88847d44660279d32f605c4eeb794fc4c77886ac8252f6779e91a202d
102 Risk Score

Malware Insights

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

The critical OLE_XLM_AUTOOPEN_DEFINEDNAME heuristic indicates the presence of an Excel 4.0 Auto_Open macro, which is designed to execute automatically when the workbook is opened. The SE_ENABLE_LURE heuristic suggests the document prompts the user to enable macros. The embedded URLs are likely used to download and execute a second-stage payload. The macro sheet itself is too large to analyze directly, but the heuristics strongly suggest a downloader pattern.

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://mayread.com/aXfFF8qdsV/th.html
    • https://tpcsv.neosj.why3s.tw/XjHoDakG/th.html

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
7758cbebef832a37ce0a327fd7d893202195f03ba9b854edef74b19dbb11678f
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8349 bytes