RCE in IBM Web Server Plug-Ins For Websphere Application And Liberty

CVE-2026-8633

IBM Web Server Plug-ins for WebSphere Application Server and WebSphere Liberty 8.5, 9.0 IBM WebSphere Application Server and WebSphere Application Server Liberty are vulnerable to remote code execution in the Web Server Plug-ins, through a specially crafted request.

Vulnerability class: RCE (Remote Code Execution)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.009 (60.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 60th percentile — 60.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-8633: held from 0.008 to 0.009.

EPSS over last 30 days · oldest: 0.008 · newest: 0.009 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-8633?
CVE-2026-8633 is a critical-severity vulnerability in IBM Web Server Plug-Ins For Websphere Application And Liberty, classified under Code Injection. CVSS score: 9.8/10. Published 2026-05-26.
How severe is CVE-2026-8633?
Critical severity. CVSS v3 base score is 9.8 out of 10.