CVE-2025-12543

CRITICAL

9.6

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.

CVE Details

CVSS v3.1 Score9.6

SeverityCRITICAL

CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L

Attack VectorNETWORK

ComplexityLOW

Privileges RequiredNONE

User InteractionREQUIRED

Published1/7/2026

Last Modified3/18/2026

Sourcenvd

Honeypot Sightings0

Affected Products

redhat:build_of_apache_camelredhat:data_gridredhat:fuseredhat:jboss_enterprise_application_platformredhat:jboss_enterprise_application_platform_expansion_packredhat:process_automationredhat:single_sign-onredhat:undertow