CVE-2026-42527

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Deserialization of Untrusted Data vulnerability in Apache Camel. The default ObjectInputFilter pattern shipped with sev

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, 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). This issue affects Apache Camel: from 4.14.0 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 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.).

HIGH · CVSS 8.1 EPSS 0.00399

EPSS exploitation odds0.40% · top 68%

Schedule remediation

CVSS base score ≥ 7.0

No Sigma yet — build one → YARA rules0

Look this up elsewhere - one-click external pivots

NVD CVE.org CISA Exploit-DB GitHub PoC VulnCheck KEV GreyNoise

▸ How to read a CVE - triage first, then detect and patch

This page is every public fact about CVE-2026-42527, cross-linked. Its job is to answer one question fast - does this need my attention now? - and then hand you the two things you do about it. Here is how an analyst reads it.

Triage: should I act now? Four signals, and they are not interchangeable:

CVSSseverity - how bad it is IF exploited, 0-10. A high CVSS alone is not urgency; a flaw can be a perfect 10 and never actually be attacked. EPSSprobability - a model’s estimate of the chance it is exploited in the next 30 days, 0-1. This is the “will it actually happen” signal. CISA KEVconfirmed - it is being exploited in the wild right now. The strongest signal on the page; KEV beats any score. Weaponisedavailability - public exploits / PoCs, and especially Metasploit modules rated Excellent / Great. Reliable, packaged exploit code means low-skill attackers can use it today.

How they combine: KEV, or a dependable Metasploit module, means patch now regardless of CVSS. High CVSS + low EPSS + no exploit is real but not an emergency - schedule it. Low CVSS but KEV-listed still gets patched now. The verdict above already weighed these for you; this is how it got there.

Then what - two workflows:

Detectwhen you cannot patch today, follow this CVE to the ATT&CK techniques it enables, then Build a SIEM detection (the green button) - author a rule, test it in Atomic, deploy it. That buys visibility while the patch waits. PatchAffected products / packages tell you if you are exposed; Fixed versions by distribution and Vendor advisories give the exact version that closes it.

Reading order for the panels below: verdict + badges, then Public exploits / Metasploit (is it weaponised), then ATT&CK techniques + Sigma / IDS rules (can I detect it), then Affected products / packages + Fixed versions (am I exposed, what patches it), then Threat actors / IOCs (who uses it), then Scoring & timeline / references (the evidence).

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Severity & exploitation scoring

View on NVD →

CVSS base score

8.1

HIGHCVSS v3.1 · [email protected]

EPSS exploitation probability

0.40%

Top 68%odds of exploitation in the next 30 days

CVSS metric silhouette

shape grows toward worst-case

SSVC triage · cisa-vulnrichment

Exploitation

none

Automatable

Tech impact

total

CVSS vector breakdown

Exploitability - how they get in

Attack Vector

Network Adjacent Local Physical

Attack Complexity

Low High

Privileges Required

None Low High

User Interaction

None Required

Scope

Unchanged Changed

Impact - what breaks

Confidentiality

None Low High

Integrity

None Low High

Availability

None Low High

VECTORCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack path

Full kill chain

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ATT&CK techniques

Techniques this CVE enables. Pills with a solid outline are high confidence - named directly in ATT&CK or Nuclei, or human-curated by CTID; the rest are inferred from the weakness type using MITRE's CVE Mapping Methodology and the CWE → CAPEC chain. Broad, generic-weakness guesses are filtered out. A small N× marks a technique that N independent sources agree on.

T1059 · Command and Scripting Interpreter

▤ Build a SIEM detection for these techniques