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

Static analysis result for SHA-256 c6cf32d9ff31d3c5…

MALICIOUS

Office (OLE) / .XLS

279.0 KB Created: 2020-11-28 13:42:19 Authoring application: Microsoft Excel
MD5: c8d276c37cb8aec3c5dd3d6b7553fdcc SHA-1: 9e62578e38976f148402af43ce668412a4185abd SHA-256: c6cf32d9ff31d3c57c4f14deb103d15221512dc2aeab3aa5cc6b99053f4939af
80 Risk Score

Malware Insights

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

The sample is an Excel 4.0 workbook containing an Auto_Open macro that utilizes dangerous functions, specifically the RUN function, to execute code. The macro is designed to leverage a URL shortener, which likely leads to the download and execution of a second-stage payload. While the extracted URL is currently flagged as benign, the overall behavior indicates a malicious downloader.

Heuristics 4

  • XLM Auto_Open with dangerous formula APIs high 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.
  • XLM workbook contains URL shortener medium OLE_XLM_URL_SHORTENER
    Workbook contains an Excel 4.0 macro-sheet marker and visible URL-shortener targets in the OLE bytes. This is a common XLM downloader shape even when formula recovery is incomplete.
  • 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.
  • 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://tinyurl.com/y3p6uhro�
    • https://tinyurl.com/y3p6uhro

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
645b2ab32293c646d6aa34b8f46cf19d1ac92e3ca6cd1b75ac825c9914edda47
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 2060 bytes