Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 270c390e3881b588…

MALICIOUS

Office (OLE)

90.5 KB Created: 2020-07-13 15:38:54 Authoring application: Microsoft Excel
MD5: b0beb28b535080c00fc2f628f00c4499 SHA-1: f15eb3581647623e661c11c7ace8a02a0fda3c24 SHA-256: 270c390e3881b58882389e9c87b60115166a833eb2c1c5f9ad1d660a50f517a9
140 Risk Score

Malware Insights

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

The critical heuristics OLE_XLM_AUTOOPEN and OLE_XLM_DANGEROUS_FN indicate the presence of an Excel 4.0 macro sheet with an Auto_Open entry that calls dangerous functions. The extracted macro content reveals a reconstructed URL, 'http://sorbeingduq.cmlBvkFzxURLMONdwATJCSE\QYGKyIfZVP', which is likely used to download and execute a second-stage payload. This indicates a macro-based download and execution attack pattern.

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
79ebf0757562d1e83eb3472d300d129c116d934b1de308e1e2d28b8128a158ae
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 22745 bytes