CVE-2026-5516 PUBLISHED

IBM WebSphere Application Server Liberty is affected by a security bypass vulnerability

Assigner: ibm
Reserved: 03.04.2026 Published: 27.05.2026 Updated: 27.05.2026

IBM WebSphere Application Server - Liberty 22.0.0.11 through 26.0.0.5 IBM WebSphere Application Server Liberty could allow a remote attacker to bypass security under limited conditions by exploiting a specific timing window.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N
CVSS Score: 4.4

Product Status

Vendor IBM
Product WebSphere Application Server - Liberty
Versions
  • affected from 22.0.0.11 to 26.0.0.5 (incl.)

Solutions

IBM strongly recommends addressing the vulnerability now by applying a currently available interim fix or fix pack that contains the fix for APAR PH70798. To determine if a feature is enabled for IBM WebSphere Application Server Liberty, refer to How to determine if Liberty is using a specific feature https://www.ibm.com/support/pages/node/6553910 . 

For IBM WebSphere Application Server Liberty 22.0.0.11 - 26.0.0.5 using the appSecurity-3.0, appSecurity-4.0 or appSecurity-5.0 feature(s):  · Upgrade to minimal fix pack levels as required by the interim fix and then apply the Interim Fix that resolves PH70798 https://www.ibm.com/support/pages/node/7273239 --OR-- · Apply Liberty Fix Pack 26.0.0.6 or later (targeted availability 3Q2026). 

Additional interim fixes may be available and linked off the interim fix download page.

References