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

Static analysis result for SHA-256 513a6acc21682198…

MALICIOUS

Office (OLE) / .XLS

70.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-07
MD5: 65890a8a4e2d46aa256bc5c9392220f4 SHA-1: 383ad4d4782e1273c7694f818b0e861ed750e3a0 SHA-256: 513a6acc21682198ae396843242867976842dfc85084707794ed048f563b336f
140 Risk Score

Malware Insights

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

The file contains Excel 4.0 macros, specifically an Auto_Open function, which is a critical indicator of malicious intent. The macro attempts to execute a series of concatenated URLs, including 'https://national-oop.org/css/8wv7lB5/' and 'https://lightmyfire.in/demo/RIkAfgTFVuaI05r2/', likely to download and execute a second-stage payload. The presence of dangerous formula APIs like RUN further supports this assessment.

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
b4f0a647cf6176132ebc9ecde0dbe63bae14d0fc3c1b3805926fc56fef0b0f6a
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 7650 bytes