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

Static analysis result for SHA-256 0625bea68b6be5ad…

MALICIOUS

Office (OLE) / .XLSX

165.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 82589d9a919f075696df375c40336a39 SHA-1: bbba3b010249ed38877081654472cf195add80ea SHA-256: 0625bea68b6be5ad9ed6db90bec12edda258780979e7e4c7792604c41d4c3905
142 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution

The file contains Excel 4.0 macros, specifically an Auto_Open macro, which is a known technique for executing malicious code. The macros attempt to register a function using 'URLD' and then execute it, likely to download and run a second-stage payload from the URL 'http://artifkt.com/okmobi/certificate'. The use of the RUN API and the registration of external functions indicate a high likelihood of malicious intent.

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.
  • 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.
  • 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 http://www.iec.ch
    • http://ns.adobe.com/xap/1.0/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/sType/ResourceEvent#
    • http://ns.adobe.com/xap/1.0/sType/ResourceRef#
    • http://ns.adobe.com/photoshop/1.0/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
bd262aef1b7122092a6dba2320a0d0734ca374097f0b62238d07ad999ce07250
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 1994 bytes