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

Static analysis result for SHA-256 e19e4b1996f4bc4e…

MALICIOUS

Office (OLE) / .XLSX

595.5 KB
MD5: 6dc0edbae3808e75a38b0c4a19a7b56a SHA-1: 79241cb2bcd443340bfd66731bf99f02b6464dea SHA-256: e19e4b1996f4bc4e29bc8be54b389c3df169ceb6c59bb84483dec7d59cdc3b2f
160 Risk Score

Malware Insights

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

This OOXML document is password-encrypted and contains an embedded Equation Editor OLE object, a known exploit carrier. The 'CVE_2018_0798_EQUATION_NATIVE_ANOMALY' heuristic indicates exploitation of CVE-2018-0798. The document likely serves as a dropper for a second-stage payload, leveraging the Equation Editor vulnerability to achieve code execution.

Heuristics 5

  • 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 document is password-encrypted medium OFFICE_ENCRYPTED_PACKAGE
    OLE container holds MS-OFFCRYPTO encrypted package (Standard Encryption (Office 2007+, AES-128)).
  • 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.