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

Static analysis result for SHA-256 071f41c6ba5d5574…

MALICIOUS

Office (OLE) / .XLS

143.0 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel
MD5: d37ea0e04f634195f4037ed049538f8f SHA-1: cf0d658c3bc33bc5bcb8f4852a7a3dc805d36860 SHA-256: 071f41c6ba5d557491c35260b8d99a5cee331d870c1fbc7756303de0eb3ba63e
180 Risk Score

Malware Insights

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

The sample is an Excel 4.0 (XLM) macro-enabled spreadsheet. Heuristics indicate the presence of an Auto_Open macro that attempts environment evasion and uses dangerous formula APIs, specifically the RUN function. The document body displays a common lure to 'Enable Editing' and 'Enable Content', suggesting the macro is intended to execute upon opening. No specific family could be identified.

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.
  • XLM Auto_Open environment-evasion HALT gate high OLE_XLM_ENVIRONMENT_EVASION_HALT
    Excel 4.0 macro sheet auto-executes multiple GET.WORKSPACE / GET.WINDOW environment checks and halts execution when the host does not match the expected user environment. This is a common sandbox-evasion pattern in XLM malware and is stronger than a bare XLM macro-sheet indicator.
  • 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.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
1627529e29cff1e23262166bba8f7208688d7c3c8166131a39f2246e8d449339
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 172610 bytes