CVE-2025-12543
Jan. 8, 2026, 11:15 p.m.
9.6
Critical
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.
Product(s) Impacted
| Vendor | Product | Versions |
|---|---|---|
| Redhat |
|
|
Weaknesses
Common security weaknesses mapped to this vulnerability.
CWE-20
Improper Input Validation
The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.
*CPE(s)
Affected systems and software identified for this CVE.
| Type | Vendor | Product | Version | Update | Edition | Language | Software Edition | Target Software | Target Hardware | Other Information |
|---|---|---|---|---|---|---|---|---|---|---|
| a | redhat | wildfly | / | / | / | / | / | / | / | / |
| a | redhat | jboss_eap | / | / | / | / | / | / | / | / |
| a | redhat | undertow | / | / | / | / | / | / | / | / |
Tags
CVSS Score
CVSS Data - 3.1
- Attack Vector: NETWORK
- Attack Complexity: LOW
- Privileges Required: NONE
- Scope: CHANGED
- Confidentiality Impact: HIGH
- Integrity Impact: HIGH
- Availability Impact: LOW
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L
Timeline
Published: Jan. 7, 2026, 5:15 p.m.
Last Modified: Jan. 8, 2026, 11:15 p.m.
Last Modified: Jan. 8, 2026, 11:15 p.m.
Status : Awaiting Analysis
CVE has been recently published to the CVE List and has been received by the NVD.
More infoSource
secalert@redhat.com
*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.