CVE-2026-85254Apache Camel: Camel-Platform-HTTP Request-Header Echo Suppression Bypassed by Header-Name Casing

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.

Affected products (as reported)

References

• Apache Camel Security Advisory - CVE-2026-85254 vendor-advisory
• CAMEL-24453 issue-tracking
• Fix on main, released in 4.23.0 (commit 126c79bdf3f171184461f987c143b5a818df4d81) patch
• Backport to camel-4.22.x, released in 4.22.1 (commit 260989268cbc6d258b1fcba63770be8ebbec40cb) patch
• Backport to camel-4.18.x, released in 4.18.5 (commit af1efbcccf5882b1ef0094db718972da3190e7e9) patch