Camel-CXF and Camel-Knative Message Header Injection via Missing Inbound Filtering The CXF and Knative HeaderFilterStrategy implementations (CxfRsHeaderFilterStrategy in camel-cxf-rest, CxfHeaderFilterStrategy in camel-cxf-transport, and KnativeHttpHeaderFilterStrategy in camel-knative-http) only filter outbound Camel-internal headers via setOutFilterStartsWith, while not configuring inbound filtering via setInFilterStartsWith. As a result, an unauthenticated attacker can inject Camel-internal headers (e.g. CamelExecCommandExecutable, CamelFileName) via HTTP requests to CXF-RS or CXF-SOAP endpoints. When a route forwards messages from these endpoints to header-driven components such as camel-exec or camel-file, the injected headers override configured values, enabling remote code execution or arbitrary file writes. This is the same pattern that was previously addressed in camel-undertow (CVE-2025-30177), the broader incoming-header filter (CVE-2025-27636 and CVE-2025-29891), and non-HTTP strategies (CVE-2026-40453). This issue affects Apache Camel: from 3.18.0 before 4.14.6, from 4.15.0 before 4.18.2. Users are recommended to upgrade to version 4.19.0, which fixes the issue. If users are on the 4.18.x LTS releases stream, then they are suggested to upgrade to 4.18.2. If users are on the 4.14.x LTS releases stream, then they are suggested to upgrade to 4.14.6.
The HeaderFilterStrategy implementations for CXF (CxfRsHeaderFilterStrategy, CxfHeaderFilterStrategy) and Knative (KnativeHttpHeaderFilterStrategy) configure only outgoing header filtering (setOutFilterStartsWith), omitting incoming header filtering (setInFilterStartsWith). An attacker can therefore smuggle internal Camel headers — such as CamelExecCommandExecutable or CamelFileName — by embedding them directly in HTTP requests to CXF-RS or CXF-SOAP endpoints. When a Camel route passes such a crafted message to header-driven components (e.g., camel-exec, camel-file), the injected values override configured parameters, leading to execution of arbitrary system commands or file writes.
An unauthenticated remote attacker can gain the ability to execute arbitrary code on the server (RCE) or write arbitrary files to the file system, which consequently may lead to complete takeover of the vulnerable system.
Apache Camel should be updated to version 4.19.0 or later. Users of the 4.18.x LTS branch should upgrade to version 4.18.2, and users of the 4.14.x LTS branch should upgrade to version 4.14.6. Details available at: https://camel.apache.org/security/CVE-2026-47323.html
Apache Camel in versions from 3.18.0 to (excluding) 4.14.6 and from 4.15.0 to (excluding) 4.18.2, using camel-cxf-rest, camel-cxf-transport, or camel-knative-http components in combination with header-driven components (e.g., camel-exec, camel-file).
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HApache Camel
APPApache3.18.0 – 4.14.6 (bez)4.15.0 – 4.18.2 (bez)
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