CVE-2026-42253
Published: 01 June 2026
Summary
CVE-2026-42253 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Apache Activemq. Its CVSS base score is 6.1 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 46.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-33578
Vulnerability details
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Apache ActiveMQ, Apache ActiveMQ Web. The MessageServlet in the ActiveMQ web console API copies every JMS message property into an HTTP response header without any validation. This can…
more
allow overwriting and injecting security headers by setting them on JMS messages that are returned by the servlet. This issue affects Apache ActiveMQ: before 5.19.7, from 6.0.0 before 6.2.6; Apache ActiveMQ Web: before 5.19.7, from 6.0.0 before 6.2.6. Users are recommended to upgrade to version 5.19.7 or 6.2.6, which fixes the issue. The MessageServlet has now been deprecated and disabled by default.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
XSS/header injection in public-facing ActiveMQ web console directly enables exploitation of a public-facing application.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.
Validates web inputs to reject script-related content that could produce XSS.
Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.