CVE-2026-40453: The fix for CVE-2025-27636 added setLowerCase(true) to HttpHeaderFilterStrategy so that case-variant header names such as 'CAmelExecCommandExecutable'...

Description

The fix for CVE-2025-27636 added setLowerCase(true) to HttpHeaderFilterStrategy so that case-variant header names such as 'CAmelExecCommandExecutable' are filtered out alongside 'CamelExecCommandExecutable'. The same setLowerCase(true) call was not applied to five non-HTTP HeaderFilterStrategy implementations: JmsHeaderFilterStrategy and ClassicJmsHeaderFilterStrategy in camel-jms, SjmsHeaderFilterStrategy in camel-sjms, CoAPHeaderFilterStrategy in camel-coap, and GooglePubsubHeaderFilterStrategy in camel-google-pubsub. Because those strategies use case-sensitive String.startsWith('Camel'/'camel') filtering while the Camel Exchange stores headers in a case-insensitive map, an attacker with JMS (or equivalent) producer access to the broker consumed by a Camel route can inject case-variant Camel internal headers, which are then resolved by downstream components such as camel-exec and camel-file using their canonical casing. This enables remote code execution and arbitrary file write on routes that forward JMS messages to header-driven components. This issue affects Apache Camel: from 3.0.0 before 4.14.6, from 4.15.0 before 4.18.2, from 4.19.0 before 4.20.0. Users are recommended to upgrade to version 4.20.0, which fixes the issue. If users are on the 4.14.x LTS releases stream, then they are suggested to upgrade to 4.14.6. If users are on the 4.18.x releases stream, then they are suggested to upgrade to 4.18.2.

Metrics

CVSS 3.1

9.9/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS Probability

0.55%

41.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Apache	Camel	>= 3.0.0, < 4.14.6
Apache	Camel	>= 4.15.0, < 4.18.2
Apache	Camel	4.19.0

References

Timeline

Published: Apr 27, 2026
Last Modified: Jun 27, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2026-40453?

The fix for CVE-2025-27636 added setLowerCase(true) to HttpHeaderFilterStrategy so that case-variant header names such as 'CAmelExecCommandExecutable' are filtered out alongside 'CamelExecCommandExecutable'. The same setLowerCase(true) call was not applied to five non-HTTP HeaderFilterStrategy implementations: JmsHeaderFilterStrategy and ClassicJmsHeaderFilterStrategy in camel-jms, SjmsHeaderFilterStrategy in camel-sjms, CoAPHeaderFilterStrategy in camel-coap, and GooglePubsubHeaderFilterStrategy in camel-google-pubsub. Because those strategies use case-sensitive String.startsWith('Camel'/'camel') filtering while the Camel Exchange stores headers in a case-insensitive map, an attacker with JMS (or equivalent) producer access to the broker consumed by a Camel route can inject case-variant Camel internal headers, which are then resolved by downstream components such as camel-exec and camel-file using their canonical casing. This enables remote code execution and arbitrary file write on routes that forward JMS messages to header-driven components. This issue affects Apache Camel: from 3.0.0 before 4.14.6, from 4.15.0 before 4.18.2, from 4.19.0 before 4.20.0. Users are recommended to upgrade to version 4.20.0, which fixes the issue. If users are on the 4.14.x LTS releases stream, then they are suggested to upgrade to 4.14.6. If users are on the 4.18.x releases stream, then they are suggested to upgrade to 4.18.2.

How severe is CVE-2026-40453?

CVE-2026-40453 has a CVSS score of 9.9/10 (CRITICAL severity). The EPSS model estimates a 0.55% probability of exploitation in the next 30 days.

How do I fix CVE-2026-40453?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.