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

Static analysis result for SHA-256 5d34a073e711eefc…

MALICIOUS

Office (OLE) / .XLSX

269.0 KB
MD5: 6a9203346218dded19d0a8a1dee24023 SHA-1: b3497f56fecc0404d3a6e0991c8db6d76c1f4142 SHA-256: 5d34a073e711eefc35990e5f94d3eb9ff26a28e097707ed15ef9c6b421cb0aee
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The file is an encrypted Office document containing an embedded Equation Editor OLE object, which is a known exploit carrier. This indicates the sample is designed to exploit a vulnerability, likely CVE-2017-11882, to achieve arbitrary code execution on the victim's machine.

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.