THREATPORT/VULNERABILITY/CVE-2026-40466
HIGH SEVERITY

CVE-2026-40466

Activemq vulnerability

CVSS
8.8
EPSS
4.8%
EPSS pct
91th
Exploited
No known
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.
Affected vendor
Apache
Affected product
Activemq
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness type (CWE)
  • CWE-20 — Improper Input Validation
  • CWE-94 — Code Injection
Published
2026-04-24

Risk analysis

Based on its CVSS vector, this vulnerability is exploitable over the network, low attack complexity, requiring low privileges, no user interaction. Successful exploitation leads to high impact to confidentiality, high impact to integrity, high impact to availability.

Its EPSS score of 4.8% reflects a lower probability of exploitation activity in the wild over the next 30 days, placing it above 91% of all scored CVEs.

Check your external exposure to CVE-2026-40466

  • Confirm whether Apache Activemq is running on any internet-facing host or subdomain.
  • Match discovered service fingerprints against the version affected by CVE-2026-40466.
  • Prioritise remediation if the asset is public, business-critical, or near authentication/payment flows.

How ThreatPort helps with CVE-2026-40466

ThreatPort's external attack surface scanner checks your internet-facing assets — agentlessly, from the outside in — for the exposed services and versions that CVE-2026-40466 affects, then prioritises the finding by real risk using CISA KEV and FIRST.org EPSS.

Run a free external exposure scan

Are you exposed to CVE-2026-40466?

Run an instant, non-intrusive external scan to check your attack surface for CVE-2026-40466.

Start free scan

No credit card. Agentless.