The CycloneDX core module provides a model representation of the SBOM along with utilities to assist in creating, validating, and parsing SBOMs. Before deserializing CycloneDX Bill of Materials in XML format, _cyclonedx-core-java_ leverages XPath expressions to determine the schema version of the BOM. The `DocumentBuilderFactory` used to evaluate XPath expressions was not configured securely, making the library vulnerable to XML External Entity (XXE) injection. This vulnerability has been fixed in cyclonedx-core-java version 9.0.4. References: https://github.com/CycloneDX/cyclonedx-core-java/pull/434 https://github.com/CycloneDX/cyclonedx-core-java/pull/434/commits/ab0bc9c530d24f737970dbd0287d1190b129853d https://github.com/CycloneDX/cyclonedx-core-java/security/advisories/GHSA-683x-4444-jxh8