IBM WebSphere Application Server versions 9.0 and 8.5 contain a deserialization vulnerability in the Name Service component. This vulnerability is identified as CVE-2026-11711 and is classified under CWE-502. It has a CVSS v3.1 base score of 6.5, indicating a medium severity level. The vulnerability allows an attacker with network access to cause a denial of service without requiring privileges or user interaction. No information about available patches or fixes has been provided.