CVE-2025-12543

CVE-2025-12543 is a critical-severity vulnerability in Redhat Build Of Apache Camel with a CVSS 3.x base score of 9.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

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.

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 3.x base score of 9.6, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability low.
Is CVE-2025-12543 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-12543?
CVE-2025-12543 primarily affects Redhat Build Of Apache Camel. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-12543?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-12543 have an EU (EUVD) identifier?
Yes. CVE-2025-12543 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-1207.
When was CVE-2025-12543 published?
CVE-2025-12543 was published on 2026-01-07 and last updated on 2026-10-06.

References

Affected products (10)

Other CWE-20 (Improper Input Validation) vulnerabilities

Browse all CWE-20 (Improper Input Validation) vulnerabilities →