Apache Camel’s XPath component can be configured to use the InputSource document type, causing the underlying XML parser to employ the JDK's default settings. When malicious XML contains a DOCTYPE with an external entity, that entity is resolved and expanded during evaluation, allowing an attacker to read files accessible to the Camel process or force it to contact arbitrary hosts. This flaw represents an Improper Restriction of XML External Entity Reference (CWE‑611) that can significantly compromise confidentiality and potentially integrity of the system by enabling external data disclosure and influence over outbound connections.

The vulnerability affects all versions of Apache Camel from 4.0.0 up to (but not including) 4.18.5 and from 4.19.0 up to (but not including) 4.22.1. Users on the 4.18.x LTS streams should upgrade to 4.18.5, on the 4.22.x LTS streams to 4.22.1, and on all other releases to 4.23.0. The issue arises only when the XPathBuilder is configured with documentType=InputSource for expressions that process untrusted XML.

The CVSS score of 7.5 reflects a high impact, and the vulnerability has been categorized as not listed in CISA’s KEV catalog. EPSS data is unavailable, so immediate exploitation potential cannot be quantified, but the flaw is plausible in environments where external XML feeds are handled untrusted. Attackers could inject XML that resolves external entities, reading local files or initiating network traffic from the Camel process. The exploit requires the ability to supply XML to the XPath component and is facilitated by the discrepancy in parser configuration between the default type and InputSource.