Summary
CVE-2026-55993 is a high-severity Server-Side Request Forgery (SSRF) and sensitive information disclosure vulnerability in the camel-atmosphere-websocket component of Apache Camel, rated 7.5 (High) on the CVSS v3.1 scale. The flaw allows an unauthenticated remote attacker to inject Camel-internal control headers via WebSocket query parameters, redirecting server-side HTTP requests to arbitrary destinations and extracting environment variables, application properties, and vault secrets from the targeted server.
Technical details
- Root cause: The
camel-atmosphere-websocketconsumer copies all inbound WebSocket query parameters directly into the Camel Exchange header map without applying anyHeaderFilterStrategy. TheWebsocketConsumer.sendEventNotification()method iterates over the query-string map collected byWebsocketConsumer.service()and passes each entry into the Exchange without filtering the Camel header namespace. - Trigger conditions: The vulnerability is exploitable in routes where a WebSocket consumer bridges to a downstream HTTP producer, and where the WebSocket endpoint is exposed without authentication. This is a common, idiomatic routing pattern within Apache Camel.
- Attack vector: An unauthenticated remote attacker connects to the vulnerable WebSocket endpoint and supplies the
CamelHttpUri(i.e.,Exchange.HTTP_URI) Camel control header as a query parameter. - SSRF impact: The injected
CamelHttpUrivalue overrides the intended HTTP producer target, redirecting the server-side HTTP request to an attacker-chosen destination — for example, internal services or cloud instance metadata endpoints (e.g.,http://169.254.169.254/). - Secrets disclosure impact: The HTTP producer resolves Camel property placeholders on the resulting attacker-controlled URI before making the request. An attacker can embed property placeholder expressions (e.g., environment variable references, application property keys, or vault secret references) in the injected URI value; the resolved plaintext values are transmitted to the attacker-controlled destination.
Affected software
- Apache Camel (
camel-atmosphere-websocket) 4.0.0 up to and including 4.14.7 - Apache Camel (
camel-atmosphere-websocket) 4.15.0 up to and including 4.18.2 - Apache Camel (
camel-atmosphere-websocket) 4.19.0 up to and including 4.20.x
Severity
CVSS v3.1 Base Score: 7.5 (High)
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Mitigation and recommended actions
- Immediate – patch: Upgrade to one of the following fixed releases:
- 4.21.0 (latest main-line release)
- 4.14.8 (4.14.x LTS stream)
- 4.18.3 (4.18.x release stream)
- The fix enforces
HeaderFilterStrategyon inbound WebSocket header mapping, filtering the Camel header namespace case-insensitively so that externally-suppliedCamel*/camel*headers are no longer copied into the Exchange.
- If immediate upgrade is not possible – workarounds:
- Add
removeHeaders('Camel*')andremoveHeaders('camel*')processor steps at the very start of any route that begins with acamel-atmosphere-websocketconsumer, before messages reach any downstream producer. - Require authentication on all WebSocket endpoints to prevent unauthenticated access.
- Avoid routing directly from an untrusted WebSocket consumer to an HTTP producer whose target URI can be influenced by message headers.
- Add
IONIX Status
The IONIX research team is tracking ongoing exploitation attempts and recommends immediate patching. Potentially affected assets are outlined in this post.

