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Status published
Critical
CVE-2025-12543
Undertow-core: undertow http server fails to reject malformed host headers leading to potential cache poisoning and ssrf
Vulnerability Description
A flaw was found in the Undertow HTTP server core, which is used in WildFly, JBoss EAP, and other Java applications. The Undertow library fails to properly validate the Host header in incoming HTTP requests.As a result, requests containing malformed or malicious Host headers are processed without rejection, enabling attackers to poison caches, perform internal network scans, or hijack user sessions.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:
- Red Hat would like to thank Ahmet Artuç for reporting this issue.
References
- https://access.redhat.com/errata/RHSA-2026:0383
- https://access.redhat.com/errata/RHSA-2026:0384
- https://access.redhat.com/errata/RHSA-2026:0386
- https://access.redhat.com/errata/RHSA-2026:33371
- https://access.redhat.com/errata/RHSA-2026:33372
- https://access.redhat.com/errata/RHSA-2026:3889
- https://access.redhat.com/errata/RHSA-2026:3890
- https://access.redhat.com/errata/RHSA-2026:3891
- https://access.redhat.com/errata/RHSA-2026:3892
- https://access.redhat.com/errata/RHSA-2026:4915
- https://access.redhat.com/errata/RHSA-2026:4916
- https://access.redhat.com/errata/RHSA-2026:4917
- https://access.redhat.com/errata/RHSA-2026:4924
- https://access.redhat.com/security/cve/CVE-2025-12543
- https://bugzilla.redhat.com/show_bug.cgi?id=2408784
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Affected Vendor
Red Hat
View all reports →Affected Software
Red Hat build of Apache Camel 4.14.4 for Spring Boot 3.5.11, Red Hat JBoss Enterprise Application Platform, Red Hat JBoss Enterprise Application Platform 7.1 EUS for RHEL 7, Red Hat JBoss Enterprise Application Platform 7.3 EUS for RHEL 7, Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7, Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 8, Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 9, Red Hat JBoss Enterprise Application Platform 8.0, Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8, Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 9, Red Hat JBoss Enterprise Application Platform 8.1, Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8, Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9, Red Hat build of Apache Camel - HawtIO 4, Red Hat Data Grid 8, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat Fuse 7, Red Hat JBoss Enterprise Application Platform 7, Red Hat JBoss Enterprise Application Platform Expansion Pack, Red Hat Process Automation 7, Red Hat Single Sign-On 7
Vulnerable Versions:
2.2.39.Final-redhat-00001, 0:1.4.18-21.SP19_redhat_00001.1.ep7.el7, 0:2.0.41-8.SP9_redhat_00001.1.el7eap, 0:2.2.39-1.Final_redhat_00001.1.el7eap, 0:7.4.24-4.GA_redhat_00002.1.el7eap, 0:2.2.39-1.Final_redhat_00001.1.el8eap, 0:7.4.24-4.GA_redhat_00002.1.el8eap, 0:2.2.39-1.Final_redhat_00001.1.el9eap, 0:7.4.24-4.GA_redhat_00002.1.el9eap, 0:1.83.0-1.redhat_00001.1.el8eap, 0:33.0.0-2.jre_redhat_00003.1.el8eap, 0:4.0.6-1.redhat_00001.1.el8eap, 0:1.0.0-3.redhat_00009.1.el8eap, 0:2.0.2-1.Final_redhat_00001.1.el8eap, 0:2.3.23-1.SP3_redhat_00001.1.el8eap, 0:1.83.0-1.redhat_00001.1.el9eap, 0:33.0.0-2.jre_redhat_00003.1.el9eap, 0:4.0.6-1.redhat_00001.1.el9eap, 0:1.0.0-3.redhat_00009.1.el9eap, 0:2.0.2-1.Final_redhat_00001.1.el9eap, 0:2.3.23-1.SP3_redhat_00001.1.el9eap, 0:4.0.10-1.redhat_00001.1.el8eap, 0:1.82.0-1.redhat_00001.1.el8eap, 0:801.3.0-1.GA_redhat_00001.1.el8eap, 0:1.0.1-3.redhat_00003.1.el8eap, 0:6.6.36-1.Final_redhat_00001.1.el8eap, 0:4.0.2-1.Final_redhat_00001.1.el8eap, 0:2.5.0-1.redhat_00001.1.el8eap, 0:2.3.20-2.SP4_redhat_00001.1.el8eap, 0:8.1.3-4.GA_redhat_00006.1.el8eap, 0:5.0.12-1.Final_redhat_00001.1.el8eap, 0:2.6.6-1.Final_redhat_00001.1.el8eap, 0:8.1.1-4.GA_redhat_00007.1.el8eap, 0:4.0.10-1.redhat_00001.1.el9eap, 0:1.82.0-1.redhat_00001.1.el9eap, 0:801.3.0-1.GA_redhat_00001.1.el9eap, 0:1.0.1-3.redhat_00003.1.el9eap, 0:6.6.36-1.Final_redhat_00001.1.el9eap, 0:4.0.2-1.Final_redhat_00001.1.el9eap, 0:2.5.0-1.redhat_00001.1.el9eap, 0:2.3.20-2.SP4_redhat_00001.1.el9eap, 0:8.1.3-4.GA_redhat_00006.1.el9eap, 0:5.0.12-1.Final_redhat_00001.1.el9eap, 0:2.6.6-1.Final_redhat_00001.1.el9eap, 0:8.1.1-4.GA_redhat_00007.1.el9eap
Timeline
Official Publish:
January 7th, 2026
Last Modified:
July 15th, 2026
Added to House:
July 22nd, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L