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

Static analysis result for SHA-256 2ad20e9852cea2ff…

MALICIOUS

Office (OLE) / .XLSX

812.5 KB
MD5: 94e381d400557687de5ccc586117c0a4 SHA-1: 3b657f07d79d41f5836edbf80663cb243e8c1929 SHA-256: 2ad20e9852cea2fff57fc4e42bc7aed6c5a54b7c2d51f300e910aaa7cf77f91c
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution: Malicious Attachment T1559.001 Component Object Model Hijacking

The file is an encrypted Excel spreadsheet containing an embedded Equation Editor OLE object. Heuristics indicate exploitation of CVE-2018-0798 due to anomalous native stream properties within the Equation Editor object. This suggests the document is designed to exploit this vulnerability upon opening, likely to download and execute a secondary payload.

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.