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

Static analysis result for SHA-256 4a99164c0b1bbaad…

MALICIOUS

Office (OLE) / .XLS

367.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 08260a8b092850e3c99f0a9111fe0538 SHA-1: 203a2b8baeea0ac05f114b975ac030f9fe3084de SHA-256: 4a99164c0b1bbaad4bb58afe43751c04c4a8ae7f2c59e73cd5270164b9be1b06
102 Risk Score

Malware Insights

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

The sample is an Excel file containing Excel 4.0 (XLM) macros, specifically an Auto_Open defined name, which is a strong indicator of malicious intent. The document also contains a lure to enable macros, a common technique for bypassing security. The extracted URLs are likely used for downloading secondary payloads. The presence of XLM macros and the macro-enable lure suggest a downloader or droppper functionality.

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