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

Static analysis result for SHA-256 a834edb1ab8eca55…

MALICIOUS

Office (OLE) / .XLS

183.0 KB Created: 2020-10-21 04:41:26 Authoring application: Microsoft Excel
MD5: 865d8d9e76a49cb077145a42b8b818da SHA-1: c0e402d8f28e47a084669fc2515621f47b0add37 SHA-256: a834edb1ab8eca55d18997378cd86f610b05e97d8c1b40a89bea66a8902b3d7b
60 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications

The sample is an Excel 4.0 macro sheet that is encrypted, as indicated by the OLE_XLM_ENCRYPTED_MACROSHEET heuristic. The presence of an AUTOOPEN macro suggests it is designed to execute automatically upon opening. Without further deobfuscation or script content, the exact payload and delivery mechanism remain unclear, but the intent is to execute malicious code.

Heuristics 2

  • Encrypted Excel 4.0 macro sheet high OLE_XLM_ENCRYPTED_MACROSHEET
    Workbook contains an Excel 4.0 macro sheet and BIFF FILEPASS encryption. Password-protected XLM macro sheets, especially the default Excel password path, are a common malware evasion pattern because static formula extraction may fail until the workbook is decrypted.
  • 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.