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

Static analysis result for SHA-256 d5b08d278c54f8c7…

MALICIOUS

Office (OLE) / .XLSX

349.0 KB
MD5: 0012bcc9833984fe4d66b203fa320792 SHA-1: f39848e2b37a37d549a8561da8f09f581f4217ec SHA-256: d5b08d278c54f8c7e2f62ada15837a48929c569376e9f2e3160f10cb0b610472
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 object. Heuristics indicate a high likelihood of exploitation for CVE-2018-0798, an Equation Editor vulnerability. This suggests the file is designed to exploit this vulnerability to execute arbitrary code.

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.