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

Static analysis result for SHA-256 0e6655cec8316446…

MALICIOUS

Office (OLE) / .XLSX

714.0 KB
MD5: 898bc3b2d24d89289fe9a5fbcb31cfa3 SHA-1: c8816bd81c62e1a20f5ee924257b2c6301b8dc03 SHA-256: 0e6655cec8316446622c0b85dde71e6ce7c2b631e48fc48c57b51375e8bfdd7e
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The sample is a password-encrypted OOXML file containing an embedded OLE object, specifically identified as an Equation Editor exploit carrier. This strongly suggests the file is designed to leverage a known vulnerability in the Equation Editor component to achieve code execution upon opening. The presence of the embedded OLE object is the primary indicator of this attack vector.

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.