CVE-2026-43866

Home/CVE/Deserialization of Untrusted Data vulnerability in Apache Camel, Apache Camel JMS component. JmsBinding.extractBodyFrom

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Deserialization of Untrusted Data vulnerability in Apache Camel, Apache Camel JMS component. JmsBinding.extractBodyFrom

Deserialization of Untrusted Data vulnerability in Apache Camel, Apache Camel JMS component. JmsBinding.extractBodyFromJms() in camel-jms - and the equivalent JmsBinding in camel-sjms - deserializes the payload of an incoming JMS ObjectMessage via jakarta.jms.ObjectMessage.getObject() whenever the mapJmsMessage option is enabled (the default) and Camel acts as a JMS consumer. The CVE-2026-40860 hardening added a post-deserialization class check that rejects classes outside the default allow-list java.;javax.;org.apache.camel.*;!. However org.apache.camel.support.DefaultExchangeHolder itself lives in the allow-listed org.apache.camel. namespace, so an ObjectMessage whose top-level object is a DefaultExchangeHolder passes the check. The receiving side then calls DefaultExchangeHolder.unmarshal() on it without requiring the transferExchange option to be enabled - an asymmetric trust boundary, since the sending side gates ObjectMessage and transferExchange handling but the receiving side did not - writing every non-null field of the holder into the Exchange: the message body, the IN and OUT headers, the exchange properties, the variables, the exchange id and the exception. An attacker who can publish an ObjectMessage to a queue or topic consumed by an affected Camel application can therefore inject arbitrary Exchange state using only universally-trusted java.lang and java.util types, with no deserialization gadget chain required, to manipulate routing and headers, exchange properties and error handling. The same handling applies to camel-sjms and camel-sjms2, and to the JMS-family components built on JmsComponent and JmsBinding: camel-amqp, camel-activemq and camel-activemq6. This is a bypass of the CVE-2026-40860 fix rather than a flaw in it. This issue affects Apache Camel: from 3.0.0 before 4.14.8, from 4.15.0 before 4.18.3, from 4.19.0 before 4.21.0.

Apache Camel: from 3.0.0 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. After upgrading, JMS ObjectMessage handling is disabled by default in camel-jms, camel-sjms and the JMS-family components (a new objectMessageEnabled option defaults to false at the component and endpoint level), so an incoming ObjectMessage - including a DefaultExchangeHolder payload - is no longer deserialized unless the option is explicitly enabled.

only set objectMessageEnabled=true when the consumed JMS destination is fed exclusively by trusted producers. For deployments that cannot upgrade immediately, restrict publish access to the queues and topics consumed by Camel to trusted producers via JMS broker authorization, and do not expose JMS consumers that map ObjectMessage bodies to untrusted networks.

a JMS-provider deserialization allow-list does not mitigate this specific bypass because the crafted payload uses only universally-trusted classes.

HIGH · CVSS 7.3 EPSS 0.00271

EPSS exploitation odds0.27% · top 81%

Schedule remediation

SSVC automatable: yes - attacks can be scripted at scale
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-2026-43866, 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

7.3

HIGHCVSS v3.1 · [email protected]

EPSS exploitation probability

0.27%

Top 81%odds of exploitation in the next 30 days

CVSS metric silhouette

shape grows toward worst-case

SSVC triage · cisa-vulnrichment

Exploitation

none

Automatable

yes

Tech impact

partial

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:L/PR:N/UI:N/S:U/C:L/I:L/A:L

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