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

Static analysis result for SHA-256 47e4fbd274d3671a…

MALICIOUS

Office (OLE) / .XLSX

1.12 MB
MD5: 26dd3cf0ae49e5b4c9978743f829ad7c SHA-1: c521780b342709df27ab71343c11e51c8c186e77 SHA-256: 47e4fbd274d3671ae572fca56cd31889140b29534cb8aa72c78cfb3e6c87317d
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.002 Malicious File T1559 Component Object Model Hijacking T1559.001 Component Object Model Hijacking: Component Object Model Hijacking

The sample is an OOXML file that is encrypted with a default password, indicating it's likely an exploit carrier. High-severity heuristics indicate the presence of an Equation Editor OLE object, which is a common vector for exploiting vulnerabilities. The Equation Editor object contains an anomalous Ole10Native stream, suggesting it carries a payload. No document body or scripts were extracted, but the presence of the Equation Editor exploit strongly suggests a vulnerability exploitation attack pattern.

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.