Strix
26.1K

CVE-2025-12543

CRITICALCVSS 9.6/10EPSS 1.18%

Last modified

CVE-2025-12543 is a critical-severity vulnerability rated 9.6/10 on the CVSS scale. 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.. EPSS estimates a 1.18% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1
9.6/10

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

EPSS Probability
1.18%

63.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
RedhatBuild Of Apache Camel< 4.14.4
RedhatData Grid8.0
RedhatFuse7.0.0
RedhatJboss Enterprise Application Platform>= 8.0, < 8.0.12
RedhatJboss Enterprise Application Platform>= 8.1.0, < 8.1.3
RedhatJboss Enterprise Application PlatformAll versions
RedhatJboss Enterprise Application Platform7.0.0
RedhatJboss Enterprise Application Platform Expansion PackAll versions
RedhatProcess Automation7.0
RedhatSingle Sign-On7.0
RedhatUndertow< 2.2.39
RedhatUndertow>= 2.3.0, < 2.3.21

References

Timeline

Published
Last Modified
Status
Modified

Frequently Asked Questions

What is 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.
How severe is CVE-2025-12543?
CVE-2025-12543 has a CVSS score of 9.6/10 (CRITICAL severity). The EPSS model estimates a 1.18% probability of exploitation in the next 30 days.
How do I fix CVE-2025-12543?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2025-12543?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST