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

Static analysis result for SHA-256 0fbb802ae78e6cff…

MALICIOUS

Office (OLE) / .XLSX

31.0 KB Created: 2021-01-25 16:02:22 Authoring application: Microsoft Excel
MD5: 9ddf777498dffd6414903b1cf76934f0 SHA-1: 22c8ecc0557ac279943c263bf539bdecb0e6c836 SHA-256: 0fbb802ae78e6cffff6ae77af7f20a4bf856617dc869abfd5694e634c3ab377d
160 Risk Score

Malware Insights

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

The sample is an Excel 4.0 macro-enabled spreadsheet that uses an Auto_Open macro to execute. The document body contains a lure instructing the user to enable content, which is a common tactic for macro-based malware. The XLM macro sheet contains a reference to a dangerous formula API, likely for executing arbitrary code or commands.

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
ac9d68ee243c07f567b68bddbc3288c44383fbdf7cdcbbdb4644559e8274317d
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 3514 bytes