CVE-2026-64958: Apache CXF: Denial of service via message header attachments

[Colm O hEigeartaigh <coheigea () apache org>]

Severity: moderate 

Affected versions:

- Apache CXF (org.apache.cxf:cxf-core) 4.2.0 before 4.2.3
- Apache CXF (org.apache.cxf:cxf-core) 4.0.0 before 4.1.8
- Apache CXF (org.apache.cxf:cxf-core) before 3.6.12

Description:

An incomplete fix for CVE-2026-50645 means that it is still possible to perform a denial of service attack on Apache 
CXF by sending a message with many attachment headers. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 
3.6.12, which fix this issue.

Credit:

Markus Vogl, RISE GmbH (finder)

References:

https://cxf.apache.org/
https://www.cve.org/CVERecord?id=CVE-2026-64958