Login Request a demo
Medium severity · published Jun 1, 2026
CVE-2026-42253
Apache ActiveMQ, Apache ActiveMQ Web: HTTP Response Header Injection via JMS Message Properties
6.1
CVSS
1.1%
EPSS
No
On KEV
Description
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 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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)1.1% · higher than 66% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AC
ActiveMQ · Apache
before 5.19.7; 6.0.0 before 6.2.6 · source: vendor, NVD
AA
Apache ActiveMQ Web · Apache Software Foundation
before 5.19.7; 6.0.0 before 6.2.6 · source: vendor
AW
Activemq Web · Apache
before 5.19.7; 6.0.0 before 6.2.6 · source: NVD
Affected product
AC
ActiveMQ
Apache
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-42253
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-42253
Mailing List
https://lists.apache.org/thread/j9vmlc410ht5f28fc98gx75jcbq62j00
Mailing List
http://www.openwall.com/lists/oss-security/2026/05/31/17
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