CVE-2025-12543
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.
- CVSS 3.1
- 9.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H - EPSS
- 1.3% chance of exploitation in the next 30 days; higher than 70% of CVEs (scores of 2026-10-25)
- CWE
- CWE-20
- Published
- Modified
- Record from
- the NVD, synced
Affected
- redhat:build_of_apache_camel
- redhat:data_grid
- redhat:fuse
- redhat:jboss_enterprise_application_platform
- redhat:jboss_enterprise_application_platform_expansion_pack
- redhat:process_automation
- redhat:single_sign-on
- redhat:undertow
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-j382-5jj3-vw4j | Maven | io.undertow:undertow-core | 2.4.0.Alpha1 | no fix published |
| GHSA-j382-5jj3-vw4j | Maven | io.undertow:undertow-core | >=2.3.0.Alpha1 <2.3.21.Final | 2.3.21.Final |
| GHSA-j382-5jj3-vw4j | Maven | io.undertow:undertow-core | <2.2.39.Final | 2.2.39.Final |