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

Static analysis result for SHA-256 b2d7375b58cc3e37…

MALICIOUS

Office (OLE) / .XLSX

1.27 MB
MD5: 5ad185ea82c8d13241e7b2d72b3f201a SHA-1: 0d93223e92de4fa375c855459065e84889ef7cb6 SHA-256: b2d7375b58cc3e375478ec4e1b8e9e679d6024ad33bec78306a3e15597347a19
140 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1559.001 Component Object Model Hijacking

The sample is an OOXML file that is encrypted with a default password and contains embedded OLE objects, specifically identified as an Equation Editor exploit carrier. This strongly suggests the file is designed to exploit a vulnerability within the Equation Editor component to achieve code execution.

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.