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

Static analysis result for SHA-256 d930f445a9053bfe…

MALICIOUS

Office (OLE) / .XLS

31.5 KB Created: 2020-12-08 12:01:04 Authoring application: Microsoft Excel
MD5: e40c18535c48fdfe3b2e841d51c94038 SHA-1: 6e1e23e8891a8ecd8ee3d85bc77c281f4b6be63b SHA-256: d930f445a9053bfefd0cba7bf24b4ec7b267d5c498d4397d1bc694fcf0c68843
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 macro-enabled spreadsheet. Heuristics indicate the presence of an Auto_Open macro, which is a critical finding. This macro is configured to execute dangerous functions, specifically identified as 'RUN'. The document also contains a lure to enable macros, a common technique for malware delivery. No specific IOCs like URLs or hashes were extracted, but the presence of the Auto_Open function and the dangerous formula API strongly suggests the execution of arbitrary code.

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
47067ac6d4b724ae2cc018a6600b83608fd43cd58cbc37e3baa2eece65b91150
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 3775 bytes