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

Static analysis result for SHA-256 3424412893471112…

MALICIOUS

Office (OLE) / .XLSX

2.23 MB
MD5: f1b2a7e101a607da36b7886bb8d4f46b SHA-1: 587518bee9e6a8ace05b2813bee0cc0310466b72 SHA-256: 342441289347111214e0397576651f765eb1d3c994fec0ee3db593475a51c8cd
120 Risk Score

Malware Insights

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

The file is an encrypted Office document containing an embedded OLE object, specifically identified as Microsoft Equation Editor. This strongly suggests exploitation of a known vulnerability within Equation Editor to achieve arbitrary code execution. The document's encrypted nature and the presence of an exploit carrier layout further support this conclusion. The likely initial access vector is spearphishing attachment.

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.