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

Static analysis result for SHA-256 c2d763b082042e3b…

MALICIOUS

Office (OLE) / .XLS

31.0 KB Created: 2020-12-08 13:28:29 Authoring application: Microsoft Excel
MD5: 0d8d6e0f348248c30f65d05a347d73bb SHA-1: b249bd37af8844424a390401a4575e31adf7bd6a SHA-256: c2d763b082042e3b8246ced00188841fd1d180e85eb2f6f2106b7c5c55b5c906
160 Risk Score

Malware Insights

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

The file is an Excel 4.0 macro-enabled workbook. It contains an Auto_Open defined name, which is a common technique for automatically executing malicious code upon opening the document. The presence of the 'RUN' function within the macro indicates an intent to execute arbitrary commands. The 'SE_ENABLE_LURE' heuristic suggests the document likely contains a prompt to enable macros, further facilitating the execution of the malicious XLM 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
825b3846b0ebb628ac4c5a996ab22a2ca654c6ed3907bdee84eaff61f6a04f9e
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 3591 bytes