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

Static analysis result for SHA-256 cda11c8be2f8b495…

MALICIOUS

Office (OLE) / .XLSX

812.5 KB
MD5: 3afd5020edbe9735bbd497fb6444c472 SHA-1: 13ebc4141a325b09b4e63c70313f32e44a847bc4 SHA-256: cda11c8be2f8b495746e3c169ae038b9e8f857fd9945d2135a10a542ec9d867f
140 Risk Score

Malware Insights

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

The sample is an encrypted OOXML file containing an embedded Equation Editor OLE object. High-severity heuristics indicate the presence of CVE-2018-0798, an anomaly within the Equation Editor's native stream, strongly suggesting exploitation for arbitrary code execution. No document body or scripts were extractable due to encryption, but the exploitation vector is clear.

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.
  • CVE-2018-0798 — anomalous Equation Editor native stream high CVE likely CVE_2018_0798_EQUATION_NATIVE_ANOMALY
    Default-encrypted OOXML contains embedded Equation Editor data with anomalous native stream bytes consistent with a CVE-2018-0798-style exploit. This is treated as likely CVE evidence because the Equation object is malformed and payload-like.
  • 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.
  • 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.