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

Static analysis result for SHA-256 f24ac843d9cbe561…

MALICIOUS

Office (OLE) / .XLS

180.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: d4636b313205910dc464e67677acaa1c SHA-1: 32c366f2187cc5e7e637458209b33431b9fdfddf SHA-256: f24ac843d9cbe561cd8bf42c0c4e6ff4d7485d50a3068cfc36171a14d15be7c7
160 Risk Score

Malware Insights

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

The sample is an Excel 4.0 spreadsheet containing an Auto_Open macro, indicated by the OLE_XLM_AUTOOPEN and OLE_XLM_AUTOOPEN_DEFINEDNAME heuristics. The macro uses dangerous functions, including RUN, to execute code. The SE_ENABLE_LURE heuristic confirms the document attempts to trick the user into enabling macros. The extracted URLs are likely used to download and execute a second-stage payload.

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.
  • 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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
917baaae0e48794e5eb73ae3d5cf93c43110b97da5df3e45bc2f236b5551c875
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 27158 bytes