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

Static analysis result for SHA-256 0f701ba104a84774…

MALICIOUS

Office (OLE) / .XLSX

1.25 MB
MD5: ee1e7c5816ee1faed9f81de07a8d091b SHA-1: f9ee2820643cebe5ccb424d1ff9dacc78fb29eac SHA-256: 0f701ba104a847740c678ae7a65fa2447212d2039f1f87d095ebdac2aec8d834
160 Risk Score

Malware Insights

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

The file is a password-encrypted OOXML document that contains an Equation Editor OLE object. This object exhibits an anomaly, carrying a payload-like Ole10Native stream, which strongly suggests exploitation of a vulnerability within the Equation Editor component to achieve code execution. The presence of embedded OLE objects indicates it was likely delivered as a spearphishing attachment.

Heuristics 5

  • 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.
  • Equation Editor object carries payload-like Ole10Native stream high OLE_EQUATION_OLE10NATIVE_PAYLOAD_ANOMALY
    Default-encrypted OOXML embedded OLE object declares the Equation Editor CLSID but stores a large high-entropy Ole10Native stream with malformed package sizing. This is exploit-shaped Equation/OLE payload evidence.
  • 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.