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

Static analysis result for SHA-256 444be9cb11643315…

MALICIOUS

Office (OLE) / .XLSX

93.5 KB First seen: 2022-04-29
MD5: 6ffc9e7df20de5d39705bf3246b17581 SHA-1: fb0d68a6a450948b3978618e569632d97b40c552 SHA-256: 444be9cb116433157d82b0fd5880014e73d1d4e3181b2e199a4decb63089023e
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1559.001 Component Object Model Hijacking

The file is a password-encrypted Office document, a common technique for obfuscating malicious content. High-severity heuristics indicate the presence of an Equation Editor OLE object, which is a known exploit carrier for vulnerabilities like CVE-2017-11882. This suggests the document is designed to exploit this vulnerability upon opening 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.
  • 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.