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

Static analysis result for SHA-256 5fdb118ea3837f6c…

MALICIOUS

Office (OLE) / .XLS

373.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 91a52bfd8265969e4dba0a668c9d3c04 SHA-1: 35a110df7db5f241cc9626199f7e6eace328025c SHA-256: 5fdb118ea3837f6c0b877bab5eb3aa2de265a7492afaa232ce606785c0fc5f5f
162 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment

The sample is an Excel file containing Excel 4.0 (XLM) macros, including an Auto_Open entry. This macro sheet contains dangerous formula APIs, specifically the RUN function, indicating it is designed to execute code. The document body and extracted URLs suggest the macro is intended to download a second-stage payload from one of the provided URLs. The presence of an Auto_Open macro and the instruction to enable macros are common techniques for initial execution.

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://allproac.com/u8AwHMG0OM/alex.html
    • https://karnafulimarine.com/lmjhxNSMbf/alex.html

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
7b20680a5c8f61ed44dce4de0580631b9188f0dd2fb85ee91819a05bfb80a422
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 5292 bytes