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.

The CycloneDX JavaScript library contains the core functionality of OWASP CycloneDX for JavaScript. In 6.7.0, XML External entity injections were possible, when running the provided XML Validator on arbitrary input. This issue was fixed in version 6.7.1.

CycloneDX BOM Repository Server is a bill of materials (BOM) repository server for distributing CycloneDX BOMs. CycloneDX BOM Repository Server before version 2.0.1 has an improper input validation vulnerability leading to path traversal. A malicious user may potentially exploit this vulnerability to create arbitrary directories or a denial of service by deleting arbitrary directories. The vulnerability is resolved in version 2.0.1. The vulnerability is not exploitable with the default configuration with the post and delete methods disabled. This can be configured by modifying the `appsettings.json` file, or alternatively, setting the environment variables `ALLOWEDMETHODS__POST` and `ALLOWEDMETHODS__DELETE` to `false`.