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

Static analysis result for SHA-256 4113fcec8ddd5fa1…

MALICIOUS

Office (OLE) / .XLSX

1.16 MB
MD5: 9454a3ea2dac9225f4abc69f756846cd SHA-1: 8324929668e11b31004bc4a8202a32c116ab4072 SHA-256: 4113fcec8ddd5fa1e0a65985e3ca3082de37bc602add7ce11dc98ce4daf012b1
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1566 Phishing T1059 Command and Scripting Interpreter

The file is an encrypted OOXML document containing an embedded Equation Editor OLE object. This object appears to carry a payload within its Ole10Native stream, indicating exploitation of a vulnerability within the Equation Editor component. The primary attack vector is likely phishing, leading the user to open this malicious document and trigger the exploit.

Heuristics 4

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Default-encrypted OOXML embedded OLE object xl/embeddings/oleObject1.bin contains the Equation Editor CLSID, the legacy component exploited by CVE-2017-11882, CVE-2018-0802, and CVE-2018-0798.
  • Default-encrypted OOXML exploit carrier layout high OOXML_ENCRYPTED_EXPLOIT_CARRIER_SHAPE
    Default-password encrypted OOXML package contains embedded OLE object parts and additional activation/decoy parts. This layout is common in malicious Excel exploit delivery and requires inspecting the decrypted package.
  • Equation Editor object carries payload-like Ole10Native stream high OLE_EQUATION_OLE10NATIVE_PAYLOAD_ANOMALY
    Default-encrypted OOXML embedded OLE object declares the Equation Editor CLSID but stores a large high-entropy Ole10Native stream with malformed package sizing. This is exploit-shaped Equation/OLE payload evidence.
  • 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.