---
id: CVE-2025-12543
title: >-
  A flaw was found in the Undertow HTTP server core, which is used in WildFly,
  JBoss EAP, and other Java applications
summary: >-
  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
  containi…
severity: critical
cvss: 9.6
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L'
cwe:
  - CWE-20
vendor: redhat
product: build_of_apache_camel
affected:
  - build_of_apache_camel < 4.14.4
  - data_grid = 8.0
  - fuse = 7.0.0
  - 'jboss_enterprise_application_platform >= 8.0, < 8.0.12'
  - 'jboss_enterprise_application_platform >= 8.1.0, < 8.1.3'
  - jboss_enterprise_application_platform
  - jboss_enterprise_application_platform = 7.0.0
  - jboss_enterprise_application_platform_expansion_pack
  - process_automation = 7.0
  - single_sign-on = 7.0
  - undertow < 2.2.39
  - 'undertow >= 2.3.0, < 2.3.21'
patched:
  - build_of_apache_camel 4.14.4
  - jboss_enterprise_application_platform 8.1.3
  - undertow 2.3.21
published: '2026-01-07'
updated: '2026-06-25'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-12543'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2026:0383'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:0384'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:0386'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:3889'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:3890'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:3891'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:3892'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:4915'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:4916'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:4917'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:4924'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2025-12543'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2408784'
    label: secalert@redhat.com
tags:
  - nvd
  - exploit-available
epss: 0.01352
epssPercentile: 0.70433
ingestedAt: '2026-06-29T13:24:34.624Z'
exploits:
  github: 1
  githubRepos:
    - 'https://github.com/kavin71725/CVE-2025-12543-Fix-for-Wildfly'
  checkedAt: '2026-09-27T10:33:36.333Z'
exploitAvailable: true
---

## Overview

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.

## Affected

- `build_of_apache_camel < 4.14.4`
- `data_grid = 8.0`
- `fuse = 7.0.0`
- `jboss_enterprise_application_platform >= 8.0, < 8.0.12`
- `jboss_enterprise_application_platform >= 8.1.0, < 8.1.3`
- `jboss_enterprise_application_platform`
- `jboss_enterprise_application_platform = 7.0.0`
- `jboss_enterprise_application_platform_expansion_pack`
- `process_automation = 7.0`
- `single_sign-on = 7.0`
- `undertow < 2.2.39`
- `undertow >= 2.3.0, < 2.3.21`

## Remediation

Upgrade past the affected range:

- `build_of_apache_camel 4.14.4`
- `jboss_enterprise_application_platform 8.1.3`
- `undertow 2.3.21`