High severity · published Apr 24, 2026
CVE-2026-40466
Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ: Possible bypass of CVE-2026-34197 via HTTP discovery second-stage URI
8.8
CVSS
4.8%
EPSS
No
On KEV
Description
Improper Input Validation, Improper Control of Generation of Code ('Code Injection') vulnerability in Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ.
An authenticated attacker may bypass the fix in CVE-2026-34197 by adding a connector using an HTTP Discovery transport via BrokerView.addNetworkConnector or BrokerView.addConnector through Jolokia if the activemq-http module is on the classpath.
A malicious HTTP endpoint can return a VM transport through the HTTP URI which will bypass the validation added in CVE-2026-34197. The attacker can then use the VM transport's brokerConfig parameter to load a remote Spring XML application context using ResourceXmlApplicationContext.
Because Spring's ResourceXmlApplicationContext instantiates all singleton beans before the BrokerService validates the configuration, arbitrary code execution occurs on the broker's JVM through bean factory methods such as Runtime.exec().
This issue affects Apache ActiveMQ Broker: before 5.19.6, from 6.0.0 before 6.2.5; Apache ActiveMQ All: before 5.19.6, from 6.0.0 before 6.2.5; Apache ActiveMQ: before 5.19.6, from 6.0.0 before 6.2.5.
Users are recommended to upgrade to version 5.19.6 or 6.2.5, which fixes the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)4.8% · higher than 92% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AC
ActiveMQ · Apache
before 5.19.6; 6.0.0 before 6.2.5 · source: vendor, NVD
AA
Apache ActiveMQ All · Apache Software Foundation
before 5.19.6; 6.0.0 before 6.2.5 · source: vendor
AA
Apache ActiveMQ Broker · Apache Software Foundation
before 5.19.6; 6.0.0 before 6.2.5 · source: vendor
AB
Activemq Broker · Apache
before 5.19.6; 6.0.0 before 6.2.5 · source: NVD
RH
Red Hat JBoss Enterprise Application Platform 7 · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-40466
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40466
Not Applicable
https://activemq.apache.org/security-advisories.data/CVE-2026-34197-announcement.txt
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-40466
bugzilla.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2461410
security.access.redhat.com
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40466.json
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