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

Static analysis result for SHA-256 4ce9947cdd140d07…

MALICIOUS

Office (OLE) / .XLSX

492.5 KB
MD5: e9f54e0db17e7149c92f71b7b57d3b28 SHA-1: 7f4d1d3fbf2fd5e4eef6f3df1489c80c8e466cc9 SHA-256: 4ce9947cdd140d07ca57c71bb888a7957445720c66ae18474b7bd0620f6fcec3
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 identified as an exploit carrier. It contains an Equation Editor OLE object which exhibits anomalies consistent with CVE-2018-0798. This indicates the file is designed to exploit this vulnerability for initial 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.
  • 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.