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

Static analysis result for SHA-256 bb958395db7ceaa6…

MALICIOUS

Office (OLE) / .XLSX

595.5 KB
MD5: d998f79a63da0d20c23b03bbe908d89c SHA-1: 4a1267c0aba5ba65dc4e02befb30e36fa167a63a SHA-256: bb958395db7ceaa654257ad547db4a091658d895f7585586eae6246ed681ab29
120 Risk Score

Malware Insights

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

The sample is an OOXML file that is password-encrypted, a common technique to evade static analysis. High-severity heuristics indicate the presence of embedded OLE objects, specifically targeting the Equation Editor (CLSID offset 0x450). This strongly suggests the file is an exploit carrier designed to leverage a known vulnerability in Microsoft Equation Editor to deliver a malicious 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.
  • 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.