CVE-2026-43865
HIGHDescription
Deserialization of Untrusted Data vulnerability in Apache Camel Hazelcast component. The camel-hazelcast component creates and manages Hazelcast instances using a default configuration that applies no Java deserialization filter. When Camel builds the Hazelcast Config itself - that is, when no user-supplied HazelcastInstance, hazelcastConfigUri, or referenced Config bean is provided - neither Hazelcast's JavaSerializationFilterConfig nor a Camel-side ObjectInputFilter is configured, so objects received over the Hazelcast cluster protocol are deserialized inside Hazelcast's own serialization layer (ObjectInputStream.readObject) before Camel ever processes them. An attacker who can join or otherwise reach the Hazelcast cluster can publish a crafted serialized Java object that is then deserialized on every Camel node, resulting in remote code execution. The exposure is present by default and requires no opt-in endpoint configuration: any route using a hazelcast consumer (hazelcast-topic, hazelcast-queue, hazelcast-seda, hazelcast-map, hazelcast-multimap, hazelcast-replicatedmap, hazelcast-list, hazelcast-set), as well as the HazelcastAggregationRepository and HazelcastIdempotentRepository, is affected whenever the managed instance is created from Camel's default configuration. This issue affects Apache Camel: from 4.0.0 before 4.14.8, from 4.15.0 before 4.18.3, from 4.19.0 before 4.21.0. Users are recommended to upgrade to version 4.21.0, which fixes the issue. If users are on the 4.14.x LTS releases stream, then they are suggested to upgrade to 4.14.8. If users are on the 4.18.x releases stream, then they are suggested to upgrade to 4.18.3. The fix makes Camel apply a default Hazelcast JavaSerializationFilterConfig (whitelisting the java., javax. and org.apache.camel. class-name prefixes and blacklisting java.net.) to instances it creates from its own default configuration, while leaving any user-supplied Config or HazelcastInstance untouched. For deployments that cannot upgrade immediately, configure a deserialization filter on the Hazelcast instance (Hazelcast JavaSerializationFilterConfig, or the JVM-wide system property -Djdk.serialFilter=!java.net.**;java.**;javax.**;org.apache.camel.**;!*) and enable Hazelcast cluster authentication and TLS to restrict who can reach the cluster.
CVSS v3.1 Score
EPSS — Exploit Prediction
EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.
Weakness Type (CWE)
References
Frequently Asked Questions
What is CVE-2026-43865? +
How severe is CVE-2026-43865? +
How do I check if I'm vulnerable to CVE-2026-43865? +
Related Vulnerabilities
An authenticated user with the nx-licensing-create privilege can upload a specially crafted license file to execute arbitrary operating system commands …
A critical remote code execution (RCE) vulnerability has been reported in PTC Windchill PDMlink and PTC FlexPLM. The vulnerability may …
SEPPmail Secure Email Gateway before version 15.0.4 insecurely deserializes untrusted data, which can be reached from the new GINA UI …
Quanos SCHEMA ST4 on-premises contains a local privilege escalation vulnerability in the Client Update Service due to insecure deserialization in …
RELATE is a web-based courseware package. Prior to commit d66ba5659b459bf1ba56b7109b5f9ecf197cbefb, RELATE LMS configures its Celery workers to accept and deserialize …
A security vulnerability has been identified in the IBL Software Engineering Visual Weather and derived products (NAMIS, Aero Weather, Satellite …