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

Static analysis result for SHA-256 ba897fa495e2e41e…

MALICIOUS

Office (OLE) / .XLSX

125.0 KB First seen: 2022-08-16
MD5: 2b5f6753910537e5d6e1f9a86d637251 SHA-1: 5f66c24ccc164f7bbe594e0766c30bf8837c0a24 SHA-256: ba897fa495e2e41e7c1c1982cb8b299ef49afb46596ce06aadce13af1a21f47c
100 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment

The file is a password-encrypted Excel spreadsheet, which is a common delivery mechanism for malware. ClamAV detection indicates it is a downloader, likely intended to fetch and execute a secondary payload. The encryption prevents further static analysis of the document's content or embedded scripts.

Heuristics 3

  • ClamAV: Xls.Downloader.94c25b356b5a6cac-9978798-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.94c25b356b5a6cac-9978798-0
  • Office document is password-encrypted medium OFFICE_ENCRYPTED_PACKAGE
    OLE container holds MS-OFFCRYPTO encrypted package (Standard Encryption (Office 2007, AES)).
  • Office OOXML encrypted with default VelvetSweatshop password medium OFFICE_DEFAULT_PASSWORD_ENCRYPTED_OOXML
    OLE EncryptedPackage decrypts with Excel's built-in VelvetSweatshop password. Office opens this transparently, and malware uses it to hide OOXML exploit parts from scanners that only inspect the outer OLE container.