CVE-2026-85254 Apache Camel: Camel-Platform-HTTP Request-Header Echo Suppression Bypassed by Header-Name Casing
Attackers can bypass header suppression by varying case, enabling response splitting and cache poisoning in Apache Camel HTTP endpoints.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-85254?
CVE-2026-85254 is a medium-severity vulnerability in Apache Camel, published on 19 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Improper Handling of Case Sensitivity vulnerability in Apache Camel Platform HTTP component.
This issue affects Apache Camel: from 4.0.0 before 4.18.5, from 4.19.0 before 4.22.1.
The guard that prevents a request header being reflected into the response compared header names case sensitively, while HTTP header names are case insensitive. A caller could therefore defeat the suppression simply by varying the case of the header name. HTTP/2 makes the problem unconditional rather than optional: the protocol requires header names to be lowercase on the wire, so the comparison never matched and the suppression was inert for every request on an HTTP/2 connection. The consequence is that content the caller chose is echoed back in the response, which is the basis for response-splitting and cache-poisoning style attacks against whatever sits in front of the Camel endpoint.
Upgrade to Apache Camel 4.23.0, which fixes the issue. Users on the 4.18.x LTS releases stream should upgrade to 4.18.5. Users on the 4.22.x LTS releases stream should upgrade to 4.22.1. Request header names are now compared case insensitively, so the suppression holds regardless of casing and works under HTTP/2. For deployments that cannot upgrade immediately, strip the headers in question in front of the Camel endpoint, or remove them from the response in the route rather than relying on the built-in suppression.
Weakness: CWE-178
Which versions are affected by CVE-2026-85254?
How do I fix CVE-2026-85254?
No fix has been published for CVE-2026-85254 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-85254 being exploited?
There is no known exploitation of CVE-2026-85254 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-9jfp-c25q-rf5q.