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

Static analysis result for SHA-256 e7d76442af18fc17…

MALICIOUS

Office (OLE) / .XLSX

1.91 MB
MD5: 61c601674bb718dfbfb466c613e481ad SHA-1: f94bb9d92c0fdf08043438f3e921e1547aa60cad SHA-256: e7d76442af18fc1784adc2191d9ee6d078b3ba402a2465a6f061def541dd5138
180 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious File T1566 Phishing

The sample is an encrypted OOXML file that utilizes a default password, a common technique for obfuscating malicious content. It contains an embedded Equation Editor OLE object, which is a known exploit carrier. Specifically, the heuristics indicate a high likelihood of CVE-2018-0798 being leveraged due to anomalous Equation Editor native stream properties and a high-entropy Ole10Native payload. The encrypted nature of the document prevents further analysis of its direct content, but the presence and characteristics of the embedded exploit object strongly suggest its malicious intent.

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.
  • CVE-2018-0798 — anomalous Equation Editor native stream high CVE likely CVE_2018_0798_EQUATION_NATIVE_ANOMALY
    Default-encrypted OOXML contains embedded Equation Editor data with anomalous native stream bytes consistent with a CVE-2018-0798-style exploit. This is treated as likely CVE evidence because the Equation object is malformed and payload-like.
  • 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.

Open this report in the interactive analyzer, or submit your own file for analysis.