CVE-2026-85254
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.
Executive briefing
The source record describes: 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. The practical risk depends on whether an affected product/version is present, reachable and configured in an exploitable way. Review the affected-product evidence and linked vendor advisories before assigning exposure status.
Evidence confidence: Moderate Evidence-derived, not an exploitability verdict
Severity & attack characteristics
CVSS vector:CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Technical explanation & impact
The technical mechanism is not expanded beyond the source description unless a referenced advisory supplies additional evidence. Read the linked vendor/CERT advisories for root-cause detail.
Potential impact must be interpreted from the published CVSS impact metrics and the affected component. A CVSS impact score is not proof that a particular asset is exploitable.
Weakness classification
CWE-178Affected products and versions
Products below are parsed from NVD vulnerable CPE configuration entries. Version boundaries are shown as published; verify applicability with the vendor.
| Vendor | Product | Version evidence |
|---|---|---|
| apache | camel | from (inclusive) 4.19.0; before 4.22.1 |
Remediation & validation
- Identify exposure by comparing the affected product and version ranges with your asset inventory, SBOM and externally exposed services.
- Review the linked vendor security advisory or patch notes. Upgrade to a vendor-confirmed fixed release; do not infer a fixed version from the CVE description.
- Until patched, consider restricting network access or disabling the affected feature where operationally safe. These are temporary controls, not a substitute for a vendor fix.
- Validate the remediation with a version check and vulnerability rescan, then retain change evidence.
No fixed version is displayed unless it is explicitly established by a vendor advisory. Follow the vendor's release notes for exact product and branch applicability.
Vendor advisories, patches & exploit references
- https://camel.apache.org/security/CVE-2026-85254.html PATCH security@apache.org
- https://github.com/apache/camel/pull/25831 PATCH security@apache.org
- https://github.com/apache/camel/pull/25940 PATCH security@apache.org
- https://github.com/apache/camel/pull/25942 PATCH security@apache.org
- https://issues.apache.org/jira/browse/CAMEL-24453 ADVISORY security@apache.org