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

Static analysis result for SHA-256 aff7fc9b71bd61be…

MALICIOUS

Office (OLE) / .XLS

373.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: d3d7f7a061940008af96ba0bfee5837e SHA-1: 6665a53c78e0643d9a0e7178e44f6eed4c4fd443 SHA-256: aff7fc9b71bd61be3d7e08837588d848b61e870a2b6c57e873f8d4a40e173eb4
160 Risk Score

Malware Insights

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

The file is an Excel 4.0 spreadsheet containing an Auto_Open macro. This macro utilizes dangerous formula APIs, specifically the RUN function, to execute arbitrary code. The document body and embedded artifacts indicate that the macro is designed to prompt the user to enable content, a common lure. Once enabled, it downloads and executes a payload from one of the provided URLs.

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://techserve4u.com/utlqwePl9XKr/alex.html
    • https://evershinesoftware.com/isei5Q7KlsQ5/alex.html

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
599707db4356dee9b1659b3a18ea6968bd26a6e750ede458308d788c900c5e21
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 5292 bytes