This schema was originally developed by The MITRE Corporation. The STIX XML Schema implementation is maintained by The MITRE Corporation and developed by the open STIX Community. For more information, including how to get involved in the effort and how to submit change requests, please visit the STIX website at http://stix.mitre.org.
The CVRF1.1InstanceType provides an extension to the VulnerabilityType which imports and leverages the CVRF schema for structured characterization of Vulnerabilities. This could include characterization of 0-days or other vulnerabilities that do not have a CVE or OSVDB ID.
The @is_publicly_acknowledged field captures whether or not the vulnerability is publicly acknowledged by the vendor.
Source
<xs:complexType name="CVRF1.1InstanceType"><xs:annotation><xs:documentation>The CVRF1.1InstanceType provides an extension to the VulnerabilityType which imports and leverages the CVRF schema for structured characterization of Vulnerabilities. This could include characterization of 0-days or other vulnerabilities that do not have a CVE or OSVDB ID.</xs:documentation></xs:annotation><xs:complexContent><xs:extension base="et:VulnerabilityType"><xs:sequence><xs:element ref="cvrf:cvrfdoc"><xs:annotation><xs:documentation>The CVRF field contains the structured characterization of Vulnerabilities utilizing the CVRF schema.</xs:documentation></xs:annotation></xs:element></xs:sequence></xs:extension></xs:complexContent></xs:complexType>