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.
References
| Link | Resource |
|---|---|
| https://access.redhat.com/errata/RHSA-2026:0383 | Vendor Advisory |
| https://access.redhat.com/errata/RHSA-2026:0384 | Vendor Advisory |
| https://access.redhat.com/errata/RHSA-2026:0386 | Vendor Advisory |
| https://access.redhat.com/errata/RHSA-2026:3889 | Vendor Advisory |
| https://access.redhat.com/errata/RHSA-2026:3890 | Vendor Advisory |
| https://access.redhat.com/errata/RHSA-2026:3891 | Vendor Advisory |
| https://access.redhat.com/errata/RHSA-2026:3892 | Vendor Advisory |
| 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 | Vendor Advisory |
| https://bugzilla.redhat.com/show_bug.cgi?id=2408784 | Issue Tracking Vendor Advisory |
Configurations
Configuration 1 (hide)
|
History
No history.
Information
Published : 2026-01-07 17:15
Updated : 2026-03-18 16:16
NVD link : CVE-2025-12543
Mitre link : CVE-2025-12543
CVE.ORG link : CVE-2025-12543
JSON object : View
Products Affected
redhat
- fuse
- process_automation
- undertow
- data_grid
- jboss_enterprise_application_platform_expansion_pack
- jboss_enterprise_application_platform
- single_sign-on
- build_of_apache_camel
CWE
CWE-20
Improper Input Validation
