Apache Camel Security Advisory - CVE-2026-42527

Apache Camel security advisory: CVE-2026-42527

Severity

MEDIUM

Summary

Permissive default ObjectInputFilter pattern admits java.net.** and enables DNS-based information disclosure

Versions affected

Apache Camel 4.14.0 through 4.14.7 (4.14.x line). Apache Camel 4.18.0 through 4.18.2 (4.18.x line). Apache Camel 4.20.0.

Versions fixed

4.14.8, 4.18.3, 4.21.0.

Description

The default ObjectInputFilter pattern shipped with several Apache Camel components for defense-in-depth deserialization filtering ('java.**;javax.**;org.apache.camel.**;!*', or the no-'javax.**' variant in the aggregation-repository components) uses a recursive 'java.**' glob that admits classes whose hashCode/equals/readObject methods perform network I/O, notably java.net.URL and java.net.InetAddress. When an attacker can deliver a Java-serialized payload to an affected Camel consumer, deserialization of a HashMap (or any collection that calls hashCode on its elements) containing java.net.URL keys causes the JVM to issue DNS queries to the attacker-supplied host during the deserialization side-effect. The class-level filter check passes because the resulting object's class (HashMap) is allow-listed; the DNS query is observable on an attacker-controlled DNS server, providing an out-of-band side channel. The exposure is highest on the camel-jms family because JmsBinding.extractBodyFromJms invokes ObjectMessage.getObject() unconditionally when mapJmsMessage=true (default). Affected components: camel-jms, camel-sjms, camel-amqp, camel-mina, camel-netty, camel-netty-http, camel-vertx-http, camel-infinispan, and the aggregation repository components camel-leveldb, camel-cassandraql, camel-consul, camel-sql (JDBC aggregation repository).

Notes

The JIRA ticket: https://issues.apache.org/jira/browse/CAMEL-23372 refers to the commits that resolved the issue, and has more details.

The defective default deserialization filter was introduced by the CAMEL-23297, CAMEL-23319, CAMEL-23321, CAMEL-23322, and CAMEL-23324 hardening series. The fix was merged on main in https://github.com/apache/camel/pull/22801 (commit 1b60801edf9864465db7abf391539ee425a53e2c). Backports are tracked in https://github.com/apache/camel/pull/22813 (camel-4.18.x) and https://github.com/apache/camel/pull/22815 (camel-4.14.x).

Mitigation

Users are recommended to upgrade to a version that contains the CAMEL-23372 fix once available: 4.21.0 for the 4.21.x line, 4.18.3 for the 4.18.x line, and 4.14.8 for the 4.14.x line. For deployments that cannot upgrade immediately, configure a JMS-provider-side allow-list (Apache ActiveMQ Artemis ‘deserializationAllowList’ / ‘deserializationDenyList’, Apache ActiveMQ Classic ‘org.apache.activemq.SERIALIZABLE_PACKAGES’) as the primary mitigation, and/or override the in-code default via the endpoint-level ‘deserializationFilter’ option or the JVM-wide ‘-Djdk.serialFilter’ system property with an explicit deny: ‘!java.net.;java.;javax.;org.apache.camel.;!’ (or ‘!java.net.;java.;org.apache.camel.**;!’ for the aggregation-repository components, which do not include javax.**).

Credit

This vulnerability was reported by Venkatraman Kumar from Securin and Yu Bao from Paypal

References

PGP signed advisory data: CVE-2026-42527.txt.asc
Mitre CVE Entry: https://www.cve.org/CVERecord?id=CVE-2026-42527