Undertow-core: undertow http server fails to reject malformed host headers leading to potential cache poisoning and ssrf (Red Hat Red Hat build of Apache Camel 4.14.4 for Spring Boot 3.5.11)

CVE-2025-12543

CRITICAL 9.6

At a glance

Source: NVD
EPSS: EPSS 1.33 % · percentile 71 (2026-10-31)
State: PUBLISHED
Published: 2026-01-07 16:04 UTC
Updated: 2026-10-14 16:28 UTC
Assigner: redhat
NVD status: Modified

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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.

Weaknesses (CWE)

CWE-20 — Improper Input Validation

References

Scores

Version	Score	Vector	Scored by
CVSS 3.1	CRITICAL 9.6	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L	redhat
CVSS 3.1	CRITICAL 9.6	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L	redhat-SADP
CVSS 3.1	CRITICAL 9.6	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L	NVD · secalert@redhat.com (Secondary)
CVSS 3.1	CRITICAL 9.6	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H	NVD · nvd@nist.gov (Primary)
CVSS 3.1	CRITICAL 9.6	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L	NVD · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c (Secondary)

Advisories

GHSA-j382-5jj3-vw4j — Undertow HTTP server core doesn't properly validate the Host header in incoming HTTP requests

European references

ENISA EUVD · EUVD-2026-1207
GCVE · GCVE-0-2025-12543

Affected configurations (NVD CPE)

cpe:2.3:a:redhat:build_of_apache_camel:*:*:*:*:*:spring_boot:*:* < 4.14.4
cpe:2.3:a:redhat:data_grid:8.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:fuse:7.0.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:*:*:*:*:*:*:*:* ≥ 8.0 < 8.0.12
cpe:2.3:a:redhat:jboss_enterprise_application_platform:*:*:*:*:*:*:*:* ≥ 8.1.0 < 8.1.3
cpe:2.3:a:redhat:jboss_enterprise_application_platform:-:*:*:*:text-only:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.0.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform_expansion_pack:-:*:*:*:*:*:*:*
cpe:2.3:a:redhat:process_automation:7.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:single_sign-on:7.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:undertow:*:*:*:*:*:*:*:* < 2.2.39
cpe:2.3:a:redhat:undertow:*:*:*:*:*:*:*:* ≥ 2.3.0 < 2.3.21

Affected products

Product	Versions
Red Hat · Red Hat build of Apache Camel 4.14.4 for Spring Boot 3.5.11
Red Hat · Red Hat JBoss Enterprise Application Platform 7.1 EUS for RHEL 7	unaffected 0:1.4.18-21.SP19_redhat_00001.1.ep7.el7 < *
Red Hat · Red Hat JBoss Enterprise Application Platform 7.3 EUS for RHEL 7	unaffected 0:2.0.41-8.SP9_redhat_00001.1.el7eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 7.4.24	unaffected 2.2.39.Final-redhat-00001 < *
Red Hat · Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7	unaffected 0:2.2.39-1.Final_redhat_00001.1.el7eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7	unaffected 0:7.4.24-4.GA_redhat_00002.1.el7eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 8	unaffected 0:2.2.39-1.Final_redhat_00001.1.el8eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 8	unaffected 0:7.4.24-4.GA_redhat_00002.1.el8eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 9	unaffected 0:2.2.39-1.Final_redhat_00001.1.el9eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 9	unaffected 0:7.4.24-4.GA_redhat_00002.1.el9eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 8.0
Red Hat · Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8	unaffected 0:1.83.0-1.redhat_00001.1.el8eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8	unaffected 0:33.0.0-2.jre_redhat_00003.1.el8eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8	unaffected 0:4.0.6-1.redhat_00001.1.el8eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8	unaffected 0:1.0.0-3.redhat_00009.1.el8eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8	unaffected 0:2.0.2-1.Final_redhat_00001.1.el8eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 8	unaffected 0:2.3.23-1.SP3_redhat_00001.1.el8eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 9	unaffected 0:1.83.0-1.redhat_00001.1.el9eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 9	unaffected 0:33.0.0-2.jre_redhat_00003.1.el9eap < *
Red Hat · Red Hat JBoss Enterprise Application Platform 8.0 for RHEL 9	unaffected 0:4.0.6-1.redhat_00001.1.el9eap < *

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD

💣 Undertow-core: undertow http server fails to reject malformed host headers leading to potential cache poisoning and ssrf (Red Hat Red Hat build of Apache Camel 4.14.4 for Spring Boot 3.5.11)