Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 da84306a38bb473e…

MALICIOUS

Office (OLE)

36.5 KB Created: 2020-11-27 11:38:04 Authoring application: Microsoft Excel
MD5: b863a44ddc34320fde316dd5524958a3 SHA-1: f2087fc8eb7a9a5d766808ea96f509928e0d04ba SHA-256: da84306a38bb473e2e94662c38cc3513226ae677682a29a8ce26fdd2c701ec6e
140 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1203 Exploitation for Client Execution

The file is an Excel 4.0 macro sheet that contains an Auto_Open entry, which is a common technique for executing malicious code upon opening the workbook. The heuristics indicate the use of dangerous formula APIs, suggesting the macro is designed to perform harmful actions. No specific IOCs like URLs or file paths were extracted, but the presence of Auto_Open and dangerous functions strongly implies malicious intent.

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
fe967aa3ee3927a58867774152ce9260f8b0efac11d39b43f90ee11aa8b95a8f
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6636 bytes