Описание
Improper Restriction of XML External Entity Reference in org.cyclonedx:cyclonedx-core-java
Impact
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.
XXE injection can be exploited to exfiltrate local file content, or perform Server Side Request Forgery (SSRF) to access infrastructure adjacent to the vulnerable application.
PoC
Patches
The vulnerability has been fixed in cyclonedx-core-java version 0.9.4.
Workarounds
If feasible, applications can reject XML documents before handing them to cyclonedx-core-java for parsing. This may be an option if incoming CycloneDX BOMs are known to be in JSON format.
References
- Issue was fixed via https://github.com/CycloneDX/cyclonedx-core-java/pull/434
- Issue was introduced via https://github.com/CycloneDX/cyclonedx-core-java/commit/162aa594f347b3f612fe0a45071693c3cd398ce9
- https://owasp.org/www-community/vulnerabilities/XML_External_Entity_(XXE)_Processing
- https://cheatsheetseries.owasp.org/cheatsheets/XML_External_Entity_Prevention_Cheat_Sheet.html#xpathexpression
Ссылки
Пакеты
org.cyclonedx:cyclonedx-core-java
>= 2.1.0, < 9.0.4
9.0.4
Связанные уязвимости
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 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.