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

Static analysis result for SHA-256 a2165d6e15415bde…

MALICIOUS

Office (OLE) / .XLS

41.0 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel
MD5: 32a36f6ed63a81d1a08a5750331f86a1 SHA-1: 2b9f1555c6de0c8b67fc4c2f65cb9fc6d6271515 SHA-256: a2165d6e15415bdea3193124e7df457eda86beb1e0d3dc088101d2ccec500127
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Service Execution: Visual Basic T1059.001 Command and Scripting Interpreter: PowerShell T1059.003 Command and Scripting Interpreter: Windows Command Shell

The sample is an Excel 4.0 (XLM) macro-enabled spreadsheet. Critical heuristics indicate the presence of an Auto_Open defined name and the use of dangerous formula APIs, specifically the RUN function, which is commonly used to execute arbitrary code. No specific IOCs like URLs or hashes were extracted, but the presence of XLM macros with auto-execution capabilities strongly suggests a malicious intent to run commands or download further payloads.

Heuristics 3

  • 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.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
797e36dd399a2bb520faf4f2be8e4aaeb1958cee25ffc71de7fcddcfc09a8246
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8242 bytes