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

Static analysis result for SHA-256 ca0f9ccc85e429ba…

MALICIOUS

Office (OLE) / .XLS

367.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 392ee309c3664a054342e93ed375a4b9 SHA-1: 71427d0c6f3205b0842a9ed63bdbf322e495a11b SHA-256: ca0f9ccc85e429bab701677b2a9c43b8967dd2a830cbe38f503f9d53b19f2a0c
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 macro sheet with an Auto_Open defined name, indicating it will execute macros upon opening. The document body and heuristics confirm a lure to enable macros. The extracted URLs, 'https://escolamundoazul.com.br/ntmQmwXnc6KC/ue.html' and 'https://laresumeservice.com/wp7rTKrY/ue.html', are likely used to download and execute a second-stage payload. The XLM macro sheet itself is too truncated to determine specific actions beyond the auto-execution and URL fetching.

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 — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://escolamundoazul.com.br/ntmQmwXnc6KC/ue.html
    • https://laresumeservice.com/wp7rTKrY/ue.html

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
e0f9b32b2cf7d5bbad99732afb6eb8bf95619170305ebee6a87504bc690cca2a
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8209 bytes