Apache Camel: Improper Control of Generation of Code
CVE-2026-83531 is a high-severity improper control of generation of code vulnerability in Apache Camel from Apache, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists versions 4.18.5, 4.22.1 as the first without the flaw, so updating Apache Camel to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.85% chance of exploitation within 30 days, higher than 59% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Apache Camel to 4.18.5 or 4.22.1, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Apache | Apache Camel | 4.4.0 up to, but not including, 4.18.5; 4.19.0 up to, but not including, 4.22.1 | 4.18.5, 4.22.1 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (apache.org).
Official description
Improper Control of Generation of Code ('Code Injection'), Improper Neutralization of Special Elements used in an Expression Language Statement ('Expression Language Injection') vulnerability in Apache Camel. This issue affects Apache Camel: from 4.4.0 before 4.18.5, from 4.19.0 before 4.22.1. The dynamic-router-control endpoint, introduced in 4.4.0, lets routing participants manage Dynamic Router subscriptions by sending control messages. When it handled a subscribe or update request, DynamicRouterControlProducer took the subscription predicate and the name of the language used to compile it from the incoming message, either from the predicate and expressionLanguage fields of a DynamicRouterControlMessage body or from the CamelDynamicRouterPredicate and CamelDynamicRouterExpressionLanguage headers. DynamicRouterControlService then resolved that language from the CamelContext and compiled the expression into a Predicate, with no allow-list and no opt-in. The compiled predicate was added to the channel's rule base and evaluated against every exchange routed through the corresponding dynamic-router endpoint for as long as the subscription existed. A route that forwards messages from an external transport to the control endpoint, as shown in the component documentation for routing participants in other JVMs or applications, therefore let any actor able to send a message on that transport supply an expression of their choosing, which was evaluated with the privileges of the Camel process. Any expression language available on the classpath could be selected, including the simple language, which is always present and was the default on the header path, so removing optional expression languages from the classpath did not prevent the issue. Exploitation requires the ability to send a message on a transport whose route forwards it to a dynamic-router-control endpoint; no other authentication or user interaction is needed. Releases before 4.4.0 are not affected, because their control channel took predicate expressions only from the endpoint URI configured by the route author. Users are recommended to upgrade to version 4.23.0, which fixes the issue. If users are on the 4.22.x releases stream, then they are suggested to upgrade to 4.22.1. If users are on the 4.18.x releases stream, then they are suggested to upgrade to 4.18.5. The 4.14.x releases stream and earlier reached end of life before this issue was resolved and will not receive a fix, so deployments on those lines must move to a supported release. After upgrading, a control message that carries a predicate expression or an expression language is rejected unless the new allowPredicateFromMessage option is enabled on the dynamic-router-control endpoint; enable it only when every sender of control messages is trusted. For deployments that cannot upgrade immediately, do not forward messages from untrusted or shared transports to a dynamic-router-control endpoint. Where control messages must cross such a transport, authenticate the sender and make sure the predicate and expression language of each subscription are set by the route rather than taken from the incoming message, for example by removing the CamelDynamicRouterPredicate and CamelDynamicRouterExpressionLanguage headers and clearing the predicate and expressionLanguage fields of a DynamicRouterControlMessage before it reaches the endpoint. Removing optional expression languages from the classpath is not a sufficient workaround. As defence in depth, restrict who can send to the transports that feed the control endpoint, and on 4.23.0 and 4.22.1 set the allowedSchemes option of the dynamic-router endpoint to limit which endpoints a subscription's destinationUri may name.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Control of Generation of Code
The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.
How developers prevent this class of flaw
- Refactor your program so that you do not have to dynamically generate code.
- Run your code in a jail or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which code can be executed by your product. Examples include the Unix chroot jail and AppArmor. In general, managed code may provide some protection. This may not be a feasible solution, and it only limits the impact to the operating system; the rest of your application may still be subject to compromise. Be careful to avoid CWE-243 and other weaknesses related to jails.
- Use dynamic tools and techniques that interact with the product using large test suites with many diverse inputs, such as fuzz testing (fuzzing), robustness testing, and fault injection. The product's operation may slow down, but it should not become unstable, crash, or generate incorrect results.
More Improper Control of Generation of Code vulnerabilities (CWE-94)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
Other vulnerabilities in Apache Camel
- 7.5 High severity
- 8.8 High severity
- 8.2 High severity
- 7.5 High severity
- 7.5 High severity
- 8.2 High severity
Recent Improper Control of Generation of Code vulnerabilities
- 7.2 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 7.3 High severity
- 9.9 Critical severity
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