Medium [CVE-2026-56139] Generation of Error Message Containing Sensitive Information vulnerability in Apache Camel Undertow Component

Generation of Error Message Containing Sensitive Information vulnerability in Apache Camel Undertow Component. The camel-undertow HTTP server consumer exposes a muteException option that controls what is returned to the client when a route processing error occurs.

This option defaulted to false, whereas the other Camel HTTP server components (camel-http / camel-jetty / camel-servlet and camel-platform-http) default it to true.

With muteException=false, when a request triggers an exception during route processing the consumer writes the full Throwable stack trace into the HTTP response body as text/plain instead of returning an empty body.

Any unauthenticated client that can reach the endpoint and cause a processing error - for example by sending a malformed request body, an invalid parameter, or otherwise triggering a route-internal failure - therefore receives a complete Java stack trace.

Such a stack trace can disclose sensitive internal information, including credentials embedded in exception messages, internal host names and IP addresses, filesystem paths, dependency and version details, database and class names, and the application's internal structure, which an attacker can use to plan further attacks.