CVE-2026-34197: Apache ActiveMQ High-Severity Vulnerability

What is CVE-2026-34197?

Improper Input Validation, Improper Control of Generation of Code ('Code Injection') vulnerability in Apache ActiveMQ Broker, Apache ActiveMQ. Apache ActiveMQ Classic exposes the Jolokia JMX-HTTP bridge at /api/jolokia/ on the web console. The default Jolokia access policy permits exec operations on all ActiveMQ MBeans (org.apache.activemq:*), including BrokerService.addNetworkConnector(String) and BrokerService.addConnector(String). An authenticated attacker can invoke these operations with a crafted discovery URI that triggers 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 5.19.4, from 6.0.0 before 6.2.3; Apache ActiveMQ All: before 5.19.4, from 6.0.0 before 6.2.3; Apache ActiveMQ: before 5.19.4, from 6.0.0 before 6.2.3. Users are recommended to upgrade to version 5.19.4 or 6.2.3, which fixes the issue

Technical Analysis

Weakness Classification

This vulnerability is classified as CWE-20 — Improper Input Validation. The software does not properly validate input, allowing attackers to craft inputs that cause unexpected behavior, data corruption, or code execution.

Attack Vector Breakdown

• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: Low
• User Interaction: None
• Scope: Unchanged
• Confidentiality: High
• Integrity: High
• Availability: High

Impact Analysis

This vulnerability is exploitable over the network, meaning any system reachable via the internet or internal network is potentially at risk without physical access. The attack complexity is low, meaning exploitation does not depend on specialized conditions or race windows. Successful exploitation can result in full confidentiality breach (complete data disclosure), complete integrity compromise (data modification or code execution), total availability loss (denial of service). The software does not properly validate input, allowing attackers to craft inputs that cause unexpected behavior, data corruption, or code execution.

Exploitation Probability (EPSS): 83.5% chance of exploitation in the next 30 days (99th percentile). This places the vulnerability in the highest risk tier — immediate action is critical.

Exploit Availability

Public exploit code or proof-of-concept is available for CVE-2026-34197. This significantly increases the risk of exploitation, as attackers can use or adapt existing exploit code rather than developing their own. A public exploit reference has been identified. Organizations should treat this as an urgent patching priority.

Is CVE-2026-34197 being exploited?

Yes. CVE-2026-34197 is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, restricted to CVEs with confirmed active exploitation in the wild. CISA added this vulnerability on 2026-04-16. Inclusion in KEV triggers the patching mandate under BOD 22-01 for U.S. federal civilian agencies, with a remediation deadline of 2026-04-30. Additionally, public exploit code is available, which lowers the barrier for attackers.

How to fix CVE-2026-34197

Upgrade to the patched version of the affected Apache project. For Apache HTTP Server, download the latest release from httpd.apache.org. For other Apache projects (Struts, Tomcat, Log4j), check the project-specific security page for the fixed version and migration notes. Check the Apache Security Reports page for the specific patch or update. CISA's Known Exploited Vulnerabilities catalog requires U.S. federal agencies to remediate this vulnerability by the due date shown below under Binding Operational Directive 22-01. Private organizations should treat KEV entries as priority-one patches because active exploitation has been confirmed in the wild.

Related Vulnerabilities

Other actively exploited vulnerabilities affecting ActiveMQ or sharing the same weakness (CWE-20):

• CVE-2026-32201 (Medium 6.5) [same CWE] — Improper input validation in Microsoft Office SharePoint allows an…
• CVE-2025-20393 (Critical 10.0) [same CWE] — A vulnerability in the Spam Quarantine feature of Cisco AsyncOS Software for…
• CVE-2025-8876 (High 8.8) [same CWE] — Improper Input Validation vulnerability in N-able N-central allows OS Command…
• CVE-2025-32706 (High 7.8) [same CWE] — Improper input validation in Windows Common Log File System Driver allows an…
• CVE-2024-38475 (Unknown N/A) [same vendor] — Apache HTTP Server contains an improper escaping of output vulnerability in…

Frequently asked questions

Is CVE-2026-34197 critical?

CVE-2026-34197 has a CVSS 3.1 base score of 8.8 — High severity. It should be treated as a priority patch, especially given the active exploitation confirmed by CISA. The availability of public exploit code further increases the urgency.

Is CVE-2026-34197 being actively exploited?

Yes — CISA added CVE-2026-34197 to the Known Exploited Vulnerabilities catalog on 2026-04-16. Inclusion in KEV means CISA has confirmed in-the-wild exploitation. Public exploit code has also been identified, making exploitation accessible to a broader range of threat actors.

How do I patch CVE-2026-34197?

Apply the security update from Apache for ActiveMQ. Federal agencies must remediate by 2026-04-30 under BOD 22-01. Refer to the Apache Security Reports for the official patch.

What type of vulnerability is CVE-2026-34197?

CVE-2026-34197 is classified under CWE-20 (Improper Input Validation). The software does not properly validate input, allowing attackers to craft inputs that cause unexpected behavior, data corruption, or code execution.

What is the CVSS score for CVE-2026-34197?

CVE-2026-34197 has a CVSS 3.1 base score of 8.8, classifying it as High severity. The attack vector is Network, attack complexity is Low, and non-zero privileges are required.