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

Static analysis result for SHA-256 b0b37bf6988f9438…

MALICIOUS

Office (OLE) / .XLS

367.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 5bd28611dbdbb1f94e9b0907eaa7e2b2 SHA-1: ab8ca64f8fd6e23c2c60b18934ce1ce7ee1d534c SHA-256: b0b37bf6988f94385f7314be73792d980bc159710dff98107af08dafde065f47
102 Risk Score

Malware Insights

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

The sample is an Excel 4.0 (XLM) macro-enabled spreadsheet. It contains an Auto_Open macro, indicating it will execute automatically upon opening. The presence of an 'enable lure' heuristic suggests the document prompts the user to enable macros. The embedded URLs are likely used to download a secondary payload. The XLM macros are too complex to fully analyze statically, but the overall pattern points to a macro-based downloader.

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