CVE-2026-40466
HighExploitedApache ActiveMQ Vulnerable to Improper Input Validation and Code Injection
Published Apr 24, 2026 · Updated Oct 8, 2026 · Also known as BIT-activemq-2026-40466, DEBIAN-CVE-2026-40466, GHSA-w3w2-mpp5-92gm, ROOT-APP-MAVEN-CVE-2026-40466, UBUNTU-CVE-2026-40466
Key Facts
Patch immediately- CVE-2026-40466 is a high-severity vulnerability (CVSS 8.8 v3.1) affecting Activemq (Apache), Activemq Broker (Apache), geoserver-2.27 (chainguard) and 9 more products.
- It is exploited in the wild, listed in Industry KEV feed since May 7, 2026. No public exploit code is known.
- EPSS estimates a 4.1% probability of exploitation in the next 30 days.
- Fixed versions are available, including Activemq 5.19.6, Activemq 6.2.5, Activemq Broker 5.19.6.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
8.8
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
4.1%
Higher than 90.6% of all scored CVEs
Exploited in the wild
Yes
1 catalog listing
Public exploit code
None known
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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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | May 7, 2026 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
36 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| ActivemqApache | See advisory | 5.19.6 |
| Activemq BrokerApache | See advisory | 5.19.6 |
| geoserver-2.27chainguard | See advisory | 2.27.5-r9 |
| geoserver-2.28chainguard | See advisory | 2.28.3-r7 |
| apache-activemq-6.2minimos | See advisory | 6.2.8-r0 |
Patched Releases
Activemq
5.19.6, 6.2.5
Activemq Broker
5.19.6, 6.2.5
apache-activemq-6.2
6.2.8-r0
apache-activemq-6.2-fips
6.2.8-r0
geoserver-2.27
2.27.5-r9
geoserver-2.28
2.28.3-r7
io.root.org.apache.activemq:activemq-all
6.1.3-root.io.1, 6.1.3-root.io.2, 6.1.3-root.io.3, 6.1.3-root.io.4, 6.1.3-root.io.5, 6.1.3-root.io.6, 6.1.3-root.io.7, 6.1.3-root.io.8, 6.1.8-root.io.2, 6.1.8-root.io.3, 6.1.8-root.io.4
io.root.org.apache.activemq:activemq-broker
5.18.3-root.io.10, 5.18.3-root.io.11, 5.18.3-root.io.12, 5.18.3-root.io.7, 5.18.3-root.io.8, 5.18.3-root.io.9, 6.1.3-root.io.4, 6.1.3-root.io.5, 6.1.3-root.io.6, 6.1.3-root.io.7, 6.1.3-root.io.8, 6.1.8-root.io.1, 6.1.8-root.io.2, 6.1.8-root.io.3, 6.1.8-root.io.4
org.apache.activemq:activemq-all
5.19.6, 6.1.3-aikido.5, 6.1.3-aikido.6, 6.1.3-aikido.7, 6.1.3-aikido.8, 6.1.8-aikido.2, 6.1.8-aikido.3, 6.1.8-aikido.4, 6.2.5
org.apache.activemq:activemq-broker
5.18.3-aikido.10, 5.18.3-aikido.11, 5.18.3-aikido.12, 5.19.6, 6.1.3-aikido.5, 6.1.3-aikido.6, 6.1.3-aikido.7, 6.1.3-aikido.8, 6.1.8-aikido.1, 6.1.8-aikido.2, 6.1.8-aikido.3, 6.1.8-aikido.4, 6.2.5
org.apache.activemq:apache-activemq
5.19.6, 6.2.5
Timeline
Publicly disclosed
Apr 24, 2026
Added to Industry KEV feed
May 7, 2026
Last updated
Oct 8, 2026
Weakness Type
- CWE-20 Improper Input Validation
- CWE-94 Improper Control of Generation of Code ('Code Injection')
References
- advisoryhttps://activemq.apache.org/security-advisories.data/CVE-2026-34197-announcement.txt
- advisoryGHSA advisory
- advisoryhttps://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40466.json
- advisoryhttps://nvd.nist.gov/vuln/detail/CVE-2026-40466
- advisoryhttps://security-tracker.debian.org/tracker/CVE-2026-40466
FAQ
Common Questions.
Improper Input Validation, Improper Control of Generation of Code ('Code Injection') vulnerability in Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ.
Affected: Activemq (Apache); Activemq Broker (Apache); geoserver-2.27 (chainguard), among others. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since May 7, 2026.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Activemq 5.19.6, Activemq 6.2.5, Activemq Broker 5.19.6.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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