CVE-2026-42527: Deserialization of Untrusted Data vulnerability in Apache Camel.

Deserialization of Untrusted Data vulnerability in Apache Camel.

Deserialization of Untrusted Data vulnerability in Apache Camel. 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, ca

Description from the National Vulnerability Database, published by security@apache.org

What it means for a small business

Apache Camel runs on web servers, so this is mostly your hosting company's to fix. On shared hosting you can't patch it yourself, but you can ask.

Ask your host whether your server runs it, whether it's updated, and on what date. A good host answers that in a day.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.67%, higher than 51% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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