CVE-2026-40466 Scanner

Apache ActiveMQ is a message broker software that is widely used for sending messages between different components of an application. It is used by businesses globally to assist in integrating systems and applications with high reliability and availability. ActiveMQ is often implemented in environments where tasks such as real-time alerts, monitoring, or data transfer require quick and efficient message delivery. Companies in industries such as finance, e-commerce, transportation, and logistics rely on ActiveMQ for their enterprise-wide communication needs. Open-source by nature, it offers flexibility and is widely adopted in both small-scale and large-scale deployments. As a broker-based solution, it stands out for its ability to handle multiple languages and platforms, making it a popular choice for system architects and developers.

This vulnerability in Apache ActiveMQ allows an attacker to execute arbitrary code on the broker JVM, potentially leading to a full system compromise. The vulnerability arises from a flaw that allows a bypass of a previous security fix meant to block the "vm://" transport scheme. An attacker can exploit this by using the HTTP Discovery transport to execute code remotely when the activemq-http module is present. The attacker must have authenticated access to the Jolokia API. Such vulnerabilities are critical as they open up systems to unauthorized access, manipulation, or data theft.

Technically, the vulnerability is due to the oversight in the original security patch, which did not prevent the use of certain HTTP Discovery transport URIs. These URIs can return a transport URI that then loads a remote Spring XML application context. This leads to arbitrary code execution if used maliciously. The affected endpoint is the Jolokia API where authenticated requests can be sent, and the potential for exploitation is high, given the wide use of this module. The vulnerable parameter is the transport scheme that a malicious actor can manipulate. Notably, the vulnerability is contingent on having the activemq-http module on the classpath and authenticated access to Jolokia.

If exploited, this vulnerability can allow malicious actors to run arbitrary code on the server, leading to unauthorized access, data manipulation, or even full system compromise. The execution of arbitrary code could undermine the entire security posture of the affected environment. The exposure of sensitive data, unauthorized control over broker services, and potential disruptions in service availability are possible outcomes. Organizations could face severe reputational and financial damage if system integrity is breached.

REFERENCES

• https://activemq.apache.org/security-advisories.data/CVE-2026-40466-announcement.txt
• https://nvd.nist.gov/vuln/detail/CVE-2026-40466
• https://github.com/advisories/GHSA-w3w2-mpp5-92gm
• https://github.com/apache/activemq/pull/1918