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

Static analysis result for SHA-256 2cee245f11ddcd20…

MALICIOUS

Office (OLE) / .XLSX

454.5 KB
MD5: 8b6a9ecd1c9a576d727492b1271a50ae SHA-1: ca1a71be7906418b5b5b0f350022b92d58cb3d5c SHA-256: 2cee245f11ddcd20b860cf0869705af0fbc5f0456bfb7c1784b4710859accad3
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 Equation Editor OLE object. Heuristics indicate exploitation of CVE-2018-0798 via anomalous Equation Editor native stream, suggesting it's designed to execute arbitrary code. No document body or scripts were extractable due to encryption, but the presence of the exploit carrier and Equation Editor object strongly points to a code execution attack pattern.

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.