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

Static analysis result for SHA-256 1b3bbeb9fbb82a22…

MALICIOUS

Office (OLE) / .XLS

380.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel
MD5: d26ef700d214b75910db5ee5785c50b5 SHA-1: 991972e81f2fd1c0512c38f334ac0c9a73da5eb6 SHA-256: 1b3bbeb9fbb82a22c0fdcd6368cdceaf3c198440fcea8460175f60d8020d6f40
102 Risk Score

Malware Insights

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

The file is an Excel spreadsheet containing embedded Excel 4.0 (XLM) macros, indicated by the OLE_XLM_AUTOOPEN and OLE_XLM_AUTOOPEN_DEFINEDNAME heuristics. The SE_ENABLE_LURE heuristic suggests the document prompts the user to enable macros. The extracted URLs likely host the secondary payload. The XLM macros are designed to execute automatically upon opening the document, likely downloading and running a malicious payload from one of the provided URLs.

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