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

Static analysis result for SHA-256 f54b4f1cadee74d9…

MALICIOUS

Office (OLE) / .XLSX

93.0 KB First seen: 2022-04-21
MD5: d57a1c27b6c20a9ddecc1d5d77231908 SHA-1: 7dcdc7e8c2af7867c7cb3bb8e478a1b301f82370 SHA-256: f54b4f1cadee74d9b08b62486e45d4b5fbc084bd5a05c7120e95151a56e56cc5
160 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The sample is an encrypted Office document that contains an Equation Editor OLE object. High-severity heuristics indicate that this object is anomalous and exploits CVE-2018-0798. This vulnerability allows for arbitrary code execution when the Equation Editor is loaded. No document body or scripts were extractable due to encryption, but the presence of the exploit carrier strongly suggests a malicious intent to compromise the user's system.

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)).
  • 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.