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

Static analysis result for SHA-256 464c5a4e1aaf57bd…

MALICIOUS

Office (OLE) / .XLSX

1.19 MB
MD5: 9794a0e0e404424788c9739f23f0d88e SHA-1: 4d5de3eb3a79f204ca44e6092eb3b738e83b047c SHA-256: 464c5a4e1aaf57bd6f49778d3e0a680cc47b09570df05c4fc6a9c5c789010fea
140 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious File

The sample is a default-encrypted OOXML file identified as an exploit carrier due to its embedded Equation Editor OLE object. This object contains an anomalous Ole10Native stream, suggesting it's designed to deliver a malicious payload. The presence of the Equation Editor OLE object is a strong indicator of exploit delivery, commonly used to achieve arbitrary code execution.

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.
  • 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 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.