Bug 2408784 (CVE-2025-12543) - CVE-2025-12543 undertow-core: Undertow HTTP Server Fails to Reject Malformed Host Headers Leading to Potential Cache Poisoning and SSRF
Summary: CVE-2025-12543 undertow-core: Undertow HTTP Server Fails to Reject Malformed ...
Keywords:
Status: NEW
Alias: CVE-2025-12543
Deadline: 2026-01-09
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On: 2427892 2427893 2427894 2427895
Blocks:
TreeView+ depends on / blocked
 
Reported: 2025-10-31 06:53 UTC by OSIDB Bzimport
Modified: 2026-03-18 13:55 UTC (History)
45 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2026:0383 0 None None None 2026-01-08 16:54:56 UTC
Red Hat Product Errata RHSA-2026:0384 0 None None None 2026-01-08 16:55:19 UTC
Red Hat Product Errata RHSA-2026:0386 0 None None None 2026-01-08 16:53:58 UTC
Red Hat Product Errata RHSA-2026:3889 0 None None None 2026-03-05 13:36:19 UTC
Red Hat Product Errata RHSA-2026:3890 0 None None None 2026-03-05 13:32:50 UTC
Red Hat Product Errata RHSA-2026:3891 0 None None None 2026-03-05 13:34:51 UTC
Red Hat Product Errata RHSA-2026:3892 0 None None None 2026-03-05 13:34:22 UTC
Red Hat Product Errata RHSA-2026:4915 0 None None None 2026-03-18 13:15:15 UTC
Red Hat Product Errata RHSA-2026:4916 0 None None None 2026-03-18 13:16:51 UTC
Red Hat Product Errata RHSA-2026:4917 0 None None None 2026-03-18 13:17:06 UTC
Red Hat Product Errata RHSA-2026:4924 0 None None None 2026-03-18 13:55:36 UTC

Description OSIDB Bzimport 2025-10-31 06:53:28 UTC 
An Improper Input Validation vulnerability exists in the Undertow HTTP server (io.undertow:undertow-core) where the implementation does not return a 400 Bad Request response when receiving requests with invalid or malformed Host headers. The flaw can be exploited by remote attackers via specially crafted HTTP requests. Depending on the deployment, the issue enables web cache poisoning, session hijacking, or server-side request forgery (SSRF). Attackers may inject malicious responses into caches, steal authentication tokens, or redirect users to malicious endpoints. Successful exploitation can result in complete account takeover, widespread credential theft, or unauthorized access to internal network resources, thereby compromising confidentiality and integrity of user data.
Comment 1 errata-xmlrpc 2026-01-08 16:53:55 UTC 
This issue has been addressed in the following products:

  Red Hat JBoss Enterprise Application Platform 8.1

Via RHSA-2026:0386 https://access.redhat.com/errata/RHSA-2026:0386
Comment 2 errata-xmlrpc 2026-01-08 16:54:52 UTC 
This issue has been addressed in the following products:

  Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8

Via RHSA-2026:0383 https://access.redhat.com/errata/RHSA-2026:0383
Comment 3 errata-xmlrpc 2026-01-08 16:55:15 UTC 
This issue has been addressed in the following products:

  Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9

Via RHSA-2026:0384 https://access.redhat.com/errata/RHSA-2026:0384
Comment 5 errata-xmlrpc 2026-03-05 13:32:46 UTC 
This issue has been addressed in the following products:

  Red Hat build of Apache Camel 4.14.4 for Spring Boot 3.5.11

Via RHSA-2026:3890 https://access.redhat.com/errata/RHSA-2026:3890
Comment 6 errata-xmlrpc 2026-03-05 13:34:18 UTC 
This issue has been addressed in the following products:

  Red Hat JBoss Enterprise Application Platform 8.0

Via RHSA-2026:3892 https://access.redhat.com/errata/RHSA-2026:3892
Comment 7 errata-xmlrpc 2026-03-05 13:34:47 UTC 
This issue has been addressed in the following products:

  Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 9

Via RHSA-2026:3891 https://access.redhat.com/errata/RHSA-2026:3891
Comment 8 errata-xmlrpc 2026-03-05 13:36:14 UTC 
This issue has been addressed in the following products:

  Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8

Via RHSA-2026:3889 https://access.redhat.com/errata/RHSA-2026:3889
Comment 9 errata-xmlrpc 2026-03-18 13:15:11 UTC 
This issue has been addressed in the following products:

  Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7

Via RHSA-2026:4915 https://access.redhat.com/errata/RHSA-2026:4915
Comment 10 errata-xmlrpc 2026-03-18 13:16:47 UTC 
This issue has been addressed in the following products:

  Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 8

Via RHSA-2026:4916 https://access.redhat.com/errata/RHSA-2026:4916
Comment 11 errata-xmlrpc 2026-03-18 13:17:02 UTC 
This issue has been addressed in the following products:

  Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 9

Via RHSA-2026:4917 https://access.redhat.com/errata/RHSA-2026:4917
Comment 12 errata-xmlrpc 2026-03-18 13:55:32 UTC 
This issue has been addressed in the following products:

  Red Hat JBoss Enterprise Application Platform 7.4

Via RHSA-2026:4924 https://access.redhat.com/errata/RHSA-2026:4924
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