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

Static analysis result for SHA-256 578e4fc3dfdbaaae…

MALICIOUS

Office (OLE) / .XLS

373.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 1aaccd9dbd80368998ef600158b6ce18 SHA-1: 52381e130bb4f13a9f2d0eaa6f8e1ee4d41d480c SHA-256: 578e4fc3dfdbaaae1442a669ecfbefec2479c87dcdd8f6bb30a60f33c4644dfa
160 Risk Score

Malware Insights

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

The file contains Excel 4.0 (XLM) macros, including an Auto_Open entry, which is a critical finding. The presence of a 'Macro/content-enable lure' heuristic indicates the document likely prompts the user to enable macros. The XLM macros utilize dangerous functions such as RUN, suggesting they are designed to download and execute a second-stage payload from the provided URLs. The specific functions like 'ToFilA', 'r,DllR', 'egister', 'uSe', 'ndl', 'rver', 'l32' hint at file manipulation and potential DLL loading, further supporting the payload execution theory.

Heuristics 5

  • 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.
  • XLM Auto_Open with dangerous formula APIs critical OLE_XLM_DANGEROUS_FN
    Excel 4.0 macro sheet contains an Auto_Open / Auto_Close entry and dangerous XLM formula APIs that can invoke programs, write files, or transfer control without VBA.
  • 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://pfamilydentist.com/OgdaW8AjEF/alex.html
    • https://thevoorpret.com/wQSapbrm9WmH/alex.html

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
7eb5e48f136258965c2495a123fc1d7ae2138b901360da5008973ba86cc22008
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 5292 bytes