CVE-2026-42527
Description
A flaw was found in Apache Camel. This deserialization of untrusted data vulnerability allows a remote attacker to trigger out-of-band DNS queries to an attacker-controlled host. By sending a specially crafted Java-serialized payload to an affected Camel consumer, the system's Java Virtual Machine (JVM) can be coerced into performing DNS lookups during the deserialization process. This provides an attacker with an information disclosure side channel, with the highest risk observed in the camel-jms family of components.
Statement
Moderate: Apache Camel components are susceptible to information disclosure through deserialization of untrusted data. When an attacker provides a specially crafted Java-serialized payload to an affected Camel consumer, the default ObjectInputFilter pattern allows DNS queries to an attacker-controlled host. This vulnerability primarily impacts deployments where camel-jms is used with mapJmsMessage=true (default), enabling an out-of-band side channel for information leakage.
Mitigation
To mitigate this issue, configure a JVM-wide deserialization filter to explicitly deny `java.net` classes. This can be achieved by setting the system property `-Djdk.serialFilter='!java.net.**;java.**;javax.**;org.apache.camel.**;!*'` when starting the Java Virtual Machine. For aggregation-repository components, use `'!java.net.**;java.**;org.apache.camel.**;!*'`. This may impact functionality if legitimate deserialization of `java.net` classes is required. A restart of the affected Apache Camel application is required for the changes to take effect.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.3 | N/A | 8.1 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | High |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | Low | N/A | High |
| Integrity Impact | None | N/A | High |
| Availability Impact | None | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
cve.org: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Application Data; Unexpected State
Attackers can modify unexpected objects or data that was assumed to be safe from modification. Deserialized data or code could be modified without using the provided accessor functions, or unexpected functions could be invoked.
Availability
Technical Impact: DoS: Resource Consumption (CPU)
If a function is making an assumption on when to terminate, based on a sentry in a string, it could easily never terminate.
Other
Technical Impact: Varies by Context
The consequences can vary widely, because it depends on which objects or methods are being deserialized, and how they are used. Making an assumption that the code in the deserialized object is valid is dangerous and can enable exploitation. One example is attackers using gadget chains to perform unauthorized actions, such as generating a shell.
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